Hi,
i recently encountered a problem with one of my VP312s, it started making weird wind-like noises and crackled from time to time. When i engage the pad or switch the polarity there is a loud pop which almost clips my AD - way louder than on any of the other VP312. Also there is some microphonics when i lightly hit the frontplate with my finger. What could the problem be?
Here is what i did:
- carefully reflowed all solder joints, especially around the switches, trying not to overheat them
- checked all traces for continuity
- measured DCR as mentioned in the VPXX build assembly guide
The opamp checks out fine, works like a charm in any other of my Pres.
Any help would be much appreciated!