Shruthi XT pitch changes after a few minutes

I’ve noticed some funny behavior with my Shruthi XT - after turning it on and playing it for a few minutes, it will often suddenly become dissonant or change pitch…for example, if I’m holding a plain sounding note that’s in tune, that note may suddenly change pitch to a half step higher or become dissonant sounding as if one of the oscillator’s pitch ranges changed without my input. If I change the preset and then change back to the one I was on when the problem struck, the problem goes away and the preset again sounds normal (at least for a little while). Any ideas what could be causing this?

Could it be that your keyboard/MIDI controller sends funny MIDI messages? Spurious pitch bend or CCs?

Yeah, I think so. My MIDI keyboard (Alesis VI25) seems to be intermittently tweaking the OSC 2 range by a half-step, while other controllers I try keep it steady.

Dodgy pot? they don’t make stuff very well these days.

Get a MIDI monitor on the case and see what it’s sending.