diff --git a/src/classic/btstack_cvsd_plc.h b/src/classic/btstack_cvsd_plc.h
index 40d53a86a..d7e47e364 100644
--- a/src/classic/btstack_cvsd_plc.h
+++ b/src/classic/btstack_cvsd_plc.h
@@ -68,6 +68,7 @@ typedef struct cvsd_plc_state {
     int frame_count;
 } btstack_cvsd_plc_state_t;
 
+// All int16 audio samples are in host endiness
 void btstack_cvsd_plc_init(btstack_cvsd_plc_state_t *plc_state);
 void btstack_cvsd_plc_bad_frame(btstack_cvsd_plc_state_t *plc_state, int16_t *out); 
 void btstack_cvsd_plc_good_frame(btstack_cvsd_plc_state_t *plc_state, int16_t *in, int16_t *out);
diff --git a/src/classic/btstack_sbc_plc.h b/src/classic/btstack_sbc_plc.h
index 76c151c74..3a5ccbf7e 100644
--- a/src/classic/btstack_sbc_plc.h
+++ b/src/classic/btstack_sbc_plc.h
@@ -63,6 +63,7 @@ typedef struct sbc_plc_state {
     int     nbf;
 } btstack_sbc_plc_state_t;
 
+// All int16 audio samples are in host endiness
 void btstack_sbc_plc_init(btstack_sbc_plc_state_t *plc_state);
 void btstack_sbc_plc_bad_frame(btstack_sbc_plc_state_t *plc_state, int16_t *ZIRbuf, int16_t *out); 
 void btstack_sbc_plc_good_frame(btstack_sbc_plc_state_t *plc_state, int16_t *in, int16_t *out);