There are _NO_ standard SAMPLE rate for the SAMPLEs used in modules.
But most often the SAMPLEs are done on the rate called C-3 (which is
about 16574 Hz if you have a PAL machine). Sometimes drums are SAMPLEd
at A-3 (around 28 kHz), and some sounds are at ~8 kHz or anything else
to save space.