I was hoping someone could give me a hand troubleshooting my VRM install. Prior to install the amp had no noise, hiss, numbers were all in range. After I installed the VRM and fired it up with the switched pot at full volume everything is normal. numbers all in same ranges as before. when I turned the switched pot even a quarter of a turn lower, I got a horrible noise coming out of my speaker cab. it did not matter if there was a guitar plugged in or not. I was scared to leave the pot at that setting to take readings. I followed the recommendations of rectifier>standby>VRM>Filter cap as far as order. I grounded the VRM board by itself. Since this problem shows itself when the imputs are not even in use, I would not think it would be associated with the input layout? I am attaching a few pictures, I would appreciate any advice, or troubleshooting steps for this. I love the amp, sounds great, I wanted to control the volume levels as to not disturb the family all the time so I would love to resolve this otherwise I fear I could damage the amp. [img][img][/img][/img]
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File comment: switched pot
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File comment: VRM module
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