diff --git a/ports/raspberrypi/common-hal/audiobusio/I2SOut.c b/ports/raspberrypi/common-hal/audiobusio/I2SOut.c
index 591d71632c962..d29f50b06b827 100644
--- a/ports/raspberrypi/common-hal/audiobusio/I2SOut.c
+++ b/ports/raspberrypi/common-hal/audiobusio/I2SOut.c
@@ -19,122 +19,152 @@
 #include "bindings/rp2pio/StateMachine.h"
 
 const uint16_t i2s_program[] = {
-// ; Load the next set of samples
-//                     ;        /--- LRCLK
-//                     ;        |/-- BCLK
-//                     ;        ||
-//     pull noblock      side 0b01 ; Loads OSR with the next FIFO value or X
-    0x8880,
-//     mov x osr         side 0b01 ; Save the new value in case we need it again
-    0xa827,
-//     set y 14          side 0b01
-    0xe84e,
-// bitloop1:
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     jmp y-- bitloop1  side 0b01 [2]
-    0x0a83,
-//     out pins 1        side 0b10 [2]
-    0x7201,
-//     set y 14          side 0b11 [2]
-    0xfa4e,
-// bitloop0:
-//     out pins 1        side 0b10 [2]
-    0x7201,
-//     jmp y-- bitloop0  side 0b11 [2]
-    0x1a87,
-//     out pins 1        side 0b00 [2]
-    0x6201
+
+/* From i2s.pio:
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- LRCLK
+                    ;        |/-- BCLK
+                    ;        ||
+    pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b11 ; Save the new value in case we need it again
+    set y 14          side 0b11
+bitloop1:
+    out pins 1        side 0b10 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b00 [2]
+    set y 14          side 0b01 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b01 [2]
+    out pins 1        side 0b10 [2]
+*/
+    // Above assembled with pioasm.
+    0x9880, //  0: pull   noblock         side 3
+    0xb827, //  1: mov    x, osr          side 3
+    0xf84e, //  2: set    y, 14           side 3
+    0x7201, //  3: out    pins, 1         side 2 [2]
+    0x1a83, //  4: jmp    y--, 3          side 3 [2]
+    0x6201, //  5: out    pins, 1         side 0 [2]
+    0xea4e, //  6: set    y, 14           side 1 [2]
+    0x6201, //  7: out    pins, 1         side 0 [2]
+    0x0a87, //  8: jmp    y--, 7          side 1 [2]
+    0x7201, //  9: out    pins, 1         side 2 [2]
 };
 
+
 const uint16_t i2s_program_left_justified[] = {
-// ; Load the next set of samples
-//                     ;        /--- LRCLK
-//                     ;        |/-- BCLK
-//                     ;        ||
-//     pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
-    0x9880,
-//     mov x osr         side 0b11 ; Save the new value in case we need it again
-    0xb827,
-//     set y 14          side 0b11
-    0xf84e,
-// bitloop1:
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     jmp y-- bitloop1  side 0b01 [2]
-    0x0a83,
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     set y 14          side 0b01 [2]
-    0xea4e,
-// bitloop0:
-//     out pins 1        side 0b10 [2]
-    0x7201,
-//     jmp y-- bitloop0  side 0b11 [2]
-    0x1a87,
-//     out pins 1        side 0b10 [2]
-    0x7201
+/* From i2s_left.pio:
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                     ;        /--- LRCLK
+                     ;        |/-- BCLK
+                     ;        ||
+    pull noblock      side 0b01 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b01 ; Save the new value in case we need it again
+    set y 14          side 0b01
+bitloop1:
+    out pins 1        side 0b10 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b10 [2]
+    set y 14          side 0b11 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b01 [2]
+    out pins 1        side 0b00 [2]
+*/
+    // Above assembled with pioasm.
+    0x8880, //  0: pull   noblock         side 1
+    0xa827, //  1: mov    x, osr          side 1
+    0xe84e, //  2: set    y, 14           side 1
+    0x7201, //  3: out    pins, 1         side 2 [2]
+    0x1a83, //  4: jmp    y--, 3          side 3 [2]
+    0x7201, //  5: out    pins, 1         side 2 [2]
+    0xfa4e, //  6: set    y, 14           side 3 [2]
+    0x6201, //  7: out    pins, 1         side 0 [2]
+    0x0a87, //  8: jmp    y--, 7          side 1 [2]
+    0x6201, //  9: out    pins, 1         side 0 [2]
 };
 
 // Another version of i2s_program with the LRCLC and BCLK pin swapped
 const uint16_t i2s_program_swap[] = {
-// ; Load the next set of samples
-//                     ;        /--- BCLK
-//                     ;        |/-- LRCLK
-//                     ;        ||
-//     pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
-    0x9880,
-//     mov x osr         side 0b11 ; Save the new value in case we need it again
-    0xb827,
-//     set y 14          side 0b11
-    0xf84e,
-// bitloop1:
-//     out pins 1        side 0b01 [2]
-    0x6a01,
-//     jmp y-- bitloop1  side 0b11 [2]
-    0x1a83,
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     set y 14          side 0b10 [2]
-    0xf24e,
-// bitloop0:
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     jmp y-- bitloop0  side 0b10 [2]
-    0x1287,
-//     out pins 1        side 0b01 [2]
-    0x6a01
+/* From i2s_swap.pio:
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- BCLK
+                    ;        |/-- LRCLK
+                    ;        ||
+    pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b11 ; Save the new value in case we need it again
+    set y 14          side 0b11
+bitloop1:
+    out pins 1        side 0b01 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b00 [2]
+    set y 14          side 0b10 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b10 [2]
+    out pins 1        side 0b01 [2]
+*/
+    // Above assembled with pioasm.
+    0x9880, //  0: pull   noblock         side 3
+    0xb827, //  1: mov    x, osr          side 3
+    0xf84e, //  2: set    y, 14           side 3
+    0x6a01, //  3: out    pins, 1         side 1 [2]
+    0x1a83, //  4: jmp    y--, 3          side 3 [2]
+    0x6201, //  5: out    pins, 1         side 0 [2]
+    0xf24e, //  6: set    y, 14           side 2 [2]
+    0x6201, //  7: out    pins, 1         side 0 [2]
+    0x1287, //  8: jmp    y--, 7          side 2 [2]
+    0x6a01, //  9: out    pins, 1         side 1 [2]
 };
 
 // Another version of i2s_program_left_justified with the LRCLC and BCLK pin
 // swapped.
 const uint16_t i2s_program_left_justified_swap[] = {
-// ; Load the next set of samples
-//                     ;        /--- BCLK
-//                     ;        |/-- LRCLK
-//                     ;        ||
-//     pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
-    0x9880,
-//     mov x osr         side 0b11 ; Save the new value in case we need it again
-    0xb827,
-//     set y 14          side 0b11
-    0xf84e,
-// bitloop1:
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     jmp y-- bitloop1  side 0b10 [2]
-    0x1283,
-//     out pins 1        side 0b00 [2]
-    0x6201,
-//     set y 14          side 0b10 [2]
-    0xf24e,
-// bitloop0:
-//     out pins 1        side 0b01 [2]
-    0x6a01,
-//     jmp y-- bitloop0  side 0b11 [2]
-    0x1a87,
-//     out pins 1        side 0b01 [2]
-    0x6a01
+/* From i2s_swap_left.pio:
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- BCLK
+                    ;        |/-- LRCLK
+                    ;        ||
+    pull noblock      side 0b10 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b10 ; Save the new value in case we need it again
+    set y 14          side 0b10
+bitloop1:
+    out pins 1        side 0b01 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b01 [2]
+    set y 14          side 0b11 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b10 [2]
+    out pins 1        side 0b00 [2]
+*/
+    // Above assembled with pioasm.
+    0x9080, //  0: pull   noblock         side 2
+    0xb027, //  1: mov    x, osr          side 2
+    0xf04e, //  2: set    y, 14           side 2
+    0x6a01, //  3: out    pins, 1         side 1 [2]
+    0x1a83, //  4: jmp    y--, 3          side 3 [2]
+    0x6a01, //  5: out    pins, 1         side 1 [2]
+    0xfa4e, //  6: set    y, 14           side 3 [2]
+    0x6201, //  7: out    pins, 1         side 0 [2]
+    0x1287, //  8: jmp    y--, 7          side 2 [2]
+    0x6201, //  9: out    pins, 1         side 0 [2]
 };
 
 void i2sout_reset(void) {
diff --git a/ports/raspberrypi/common-hal/audiobusio/README.pio b/ports/raspberrypi/common-hal/audiobusio/README.pio
new file mode 100644
index 0000000000000..53c73fbc19954
--- /dev/null
+++ b/ports/raspberrypi/common-hal/audiobusio/README.pio
@@ -0,0 +1,7 @@
+.pio files right now are compiled by hand with pico-sdk/tools/pioasm and inserted into I2SOut.c
+
+i2s.pio           regular pin order, not left_justified
+i2s_left.pio      regular pin order, left_justified
+
+i2s_swap.pio      swapped pin order, not left_justified
+i2s_swap_left.pio swapped pin order, left_justified
diff --git a/ports/raspberrypi/common-hal/audiobusio/i2s.pio b/ports/raspberrypi/common-hal/audiobusio/i2s.pio
new file mode 100644
index 0000000000000..b3557eeb918a9
--- /dev/null
+++ b/ports/raspberrypi/common-hal/audiobusio/i2s.pio
@@ -0,0 +1,25 @@
+; This file is part of the CircuitPython project: https://circuitpython.org
+;
+; SPDX-FileCopyrightText: Copyright (c) 2025 Dan Halbert for Adafruit Industries
+;
+; SPDX-License-Identifier: MIT
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- LRCLK
+                    ;        |/-- BCLK
+                    ;        ||
+    pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b11 ; Save the new value in case we need it again
+    set y 14          side 0b11
+bitloop1:
+    out pins 1        side 0b10 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b00 [2]
+    set y 14          side 0b01 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b01 [2]
+    out pins 1        side 0b10 [2]
diff --git a/ports/raspberrypi/common-hal/audiobusio/i2s_left.pio b/ports/raspberrypi/common-hal/audiobusio/i2s_left.pio
new file mode 100644
index 0000000000000..4830ec420782d
--- /dev/null
+++ b/ports/raspberrypi/common-hal/audiobusio/i2s_left.pio
@@ -0,0 +1,25 @@
+; This file is part of the CircuitPython project: https://circuitpython.org
+;
+; SPDX-FileCopyrightText: Copyright (c) 2025 Dan Halbert for Adafruit Industries
+;
+; SPDX-License-Identifier: MIT
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                     ;        /--- LRCLK
+                     ;        |/-- BCLK
+                     ;        ||
+    pull noblock      side 0b01 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b01 ; Save the new value in case we need it again
+    set y 14          side 0b01
+bitloop1:
+    out pins 1        side 0b10 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b10 [2]
+    set y 14          side 0b11 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b01 [2]
+    out pins 1        side 0b00 [2]
diff --git a/ports/raspberrypi/common-hal/audiobusio/i2s_swap.pio b/ports/raspberrypi/common-hal/audiobusio/i2s_swap.pio
new file mode 100644
index 0000000000000..a7ecf94c764bc
--- /dev/null
+++ b/ports/raspberrypi/common-hal/audiobusio/i2s_swap.pio
@@ -0,0 +1,25 @@
+; This file is part of the CircuitPython project: https://circuitpython.org
+;
+; SPDX-FileCopyrightText: Copyright (c) 2025 Dan Halbert for Adafruit Industries
+;
+; SPDX-License-Identifier: MIT
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- BCLK
+                    ;        |/-- LRCLK
+                    ;        ||
+    pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b11 ; Save the new value in case we need it again
+    set y 14          side 0b11
+bitloop1:
+    out pins 1        side 0b01 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b00 [2]
+    set y 14          side 0b10 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b10 [2]
+    out pins 1        side 0b01 [2]
diff --git a/ports/raspberrypi/common-hal/audiobusio/i2s_swap_left.pio b/ports/raspberrypi/common-hal/audiobusio/i2s_swap_left.pio
new file mode 100644
index 0000000000000..4e6373dd65a1e
--- /dev/null
+++ b/ports/raspberrypi/common-hal/audiobusio/i2s_swap_left.pio
@@ -0,0 +1,25 @@
+; This file is part of the CircuitPython project: https://circuitpython.org
+;
+; SPDX-FileCopyrightText: Copyright (c) 2025 Dan Halbert for Adafruit Industries
+;
+; SPDX-License-Identifier: MIT
+
+.program i2s
+.side_set 2
+
+; Load the next set of samples
+                    ;        /--- BCLK
+                    ;        |/-- LRCLK
+                    ;        ||
+    pull noblock      side 0b10 ; Loads OSR with the next FIFO value or X
+    mov x osr         side 0b10 ; Save the new value in case we need it again
+    set y 14          side 0b10
+bitloop1:
+    out pins 1        side 0b01 [2] ; Right channel first
+    jmp y-- bitloop1  side 0b11 [2]
+    out pins 1        side 0b01 [2]
+    set y 14          side 0b11 [2]
+bitloop0:
+    out pins 1        side 0b00 [2] ; Then left channel
+    jmp y-- bitloop0  side 0b10 [2]
+    out pins 1        side 0b00 [2]