Sound on Pi is silenced when the sample period changes

When the sample period is changed on the Pi, the audio is silenced for a period of about 1/4 second.

Repro:

SOUND 1,-15,&5000,2000
FOR A%=0 TO 20:WAIT:NEXT
SYS "Sound_Configure",0,0,&17,0,0
SYS "Sound_Configure",0,0,&20,0,0

Yep, that’s basically down to limitations in the firmware. Although to be honest most other modern machines will have the same problem – it seems to be the norm nowadays that the only way to change the sample rate is to stop and start playback (which must also incur a lengthy delay to avoid pops).