Micro Moog problem

[Nebulatrip]

When i first power up the Micro Moog all is fine with playing notes up and down the keyboard and all other functions working . But then after about 5 minute warm up time, only the very lower part of the keyboard will be able to play ascending or descending notes. The rest of the keys depressed on up to the highest note will only play one note sound. I'm not sure what the problem is , but it seems like it is something that after warming up malfunctions.

[Jacob Hunt]

Ic202 in the keyboard circuit looks like a good potential starting point