diff --git a/internal_filesystem/lib/mpos/board/fri3d_2024.py b/internal_filesystem/lib/mpos/board/fri3d_2024.py
index 77dafb11..fb0ed56f 100644
--- a/internal_filesystem/lib/mpos/board/fri3d_2024.py
+++ b/internal_filesystem/lib/mpos/board/fri3d_2024.py
@@ -303,9 +303,9 @@ buzzer = PWM(Pin(46), freq=550, duty=0)
 # The DAC uses BCK (bit clock) on GPIO 2, while the microphone uses SCLK on GPIO 17
 # See schematics: DAC has BCK=2, WS=47, SD=16; Microphone has SCLK=17, WS=47, DIN=15
 i2s_pins = {
+    'ws': 47,       # Word Select / LRCLK shared between DAC and mic (mandatory)
     # Output (DAC/speaker) config
     'sck': 2,       # SCLK or BCLK - Bit Clock for DAC output (mandatory)
-    'ws': 47,       # Word Select / LRCLK shared between DAC and mic (mandatory)
     'sd': 16,       # Serial Data OUT (speaker/DAC)
     # Input (microphone) config
     'sck_in': 17,   # SCLK - Serial Clock for microphone input
diff --git a/internal_filesystem/lib/mpos/board/fri3d_2026.py b/internal_filesystem/lib/mpos/board/fri3d_2026.py
index 15313b26..9035345d 100644
--- a/internal_filesystem/lib/mpos/board/fri3d_2026.py
+++ b/internal_filesystem/lib/mpos/board/fri3d_2026.py
@@ -210,7 +210,7 @@ from machine import PWM, Pin
 i2s_pins = {
     # Output (DAC/speaker) pins
     'mck': 2,       # MCLK (mandatory)
-    'sck': 17,      # SCLK aka BCLK (optional)
+    'sck': 17,      # SCLK aka BCLK (unclear if optional or mandatory)
     'ws': 47,       # Word Select / LRCLK shared between DAC and mic (mandatory)
     'sd': 16,       # Serial Data OUT (speaker/DAC)
 }