One of my A-111 VCOs has suddenly developed an issue.   I noticed some note sound fluctations in a sequence I was running and after checking my quantiser I then checked the oscillator's tuning (normally tuning is pretty rock solid on the A111s).   

I plugged the output of the A111 into a tuner and the A111 won't hold its frequency/note pitch...it shifts randomly (plus and minus) around whatever note/frequency I dial in. The shift isn't huge, but its relatively large enough that the shift is very noticeable (around +/- 20-35 cents, sometimes a little more).

I'm assuming a component has failed or something which is destabilising the module.  I've switched the unit between racks (same issue)  and tried my other A111s on the same rail and in the same rack as the affected unit and there is no problem, so the issue is isolated to the one A111.

Any ideas

Season's greetings to all !

Steve