I think it is written around the SC series although the VSX-94 use a lot of the same commands. The problem with the VSX-94 units is that any command will "wake" the unit from standby because the processor went to sleep. It was part of conserving energy and they took it too far. The new units do not suffer from this problem. The fix for your 94 is to send a dummy command, I always set the volume to -40db and then send a power off command. This way if it was off, the vol set command will turn on and put it to a known state.

I have used the driver on a SC-27 and it works fine.

I think user NSP01 could clarify this, I think he works or worked for Pioneer.