Thanks, it's a strange behavior over all.
Here is the intialization script (what should be totally okay, it's the version I last saved in june 2022 since when it worked well) ...
Try changing those lines:
Code:
JSR getTVSystem
;;;; lda #SOUND_REGION_NTSC ;or #SOUND_REGION_PAL, or #SOUND_REGION_DENDY
sta sound_param_byte_0
Into:
Code:
LDA #1
STA skipNMI
JSR getTVSystem ; loads region instead of hardcoding it
;;;; lda #SOUND_REGION_NTSC ;or #SOUND_REGION_PAL, or #SOUND_REGION_DENDY
sta sound_param_byte_0
LDA #0
STA skipNMI
Let me know if it helps with your issue.