Today I noticed a strange behavior in my Dark Energy I. I noticed a constant modulation of the cutoff frequency. It sounds like the cutoff is being modulated by an audio-rate square wave. Of course I ruled out any bleed by whatever internal CV sources are available. The  modulation won't go away.

Maybe the CEM3394 has turned bad If so, I have a Simmons SDS-800 which I don't use which has 4x CEM3394 chips inside. Is there anything I have to consider when swapping the chip myself (apart from the obvious need to re-calibrate various parameters in the Dark Energy)

kind regards

Frank