Not sure if it's just me but the music in the EGA version of PQ1 is a bit off. The tones sort of warble and vary, even on single notes.

Anyone else had this?

I wonder if it's just an emulation problem.

It sounds better if you edit your .CONF file and change MACHINE=SVGA_S3 to read MACHINE=TANDY

The tandy PCs could generate 3 tones at once plus a white noise generator for sound effects. I've gotten it to work for most all the early Sierra games (SQ1, SQ2, PQ1, etc)