MultiMoog sustain not releasing

My multimoog has a fault the sound is now not releasing from the sustaing envelope on higher frequencies are played, octaves 4’ 2’ particulary but is fine in lower octaves, this happens for external trig aswell , does any one know which component would cause this? . Mybe somone fixed this fault on a micro or multi moog . Let me know if you can help.

Actually I traced this fault back to glide circuit when I realised the sustain doesnt release when the glide pot r251 is turned up. Seems that this fault is mainley caused by decoupling capactiors c210, c206, c214 fault is better, after swapping like capacitors with less critical areas and only only occurs at v high frequencies using the wide range, will order some new caps now.