Focusrite Voicemaster Pro - overloading when turning on

[gpateluk]

Everything is warmed up and working. I now need to calibrate the unit. It mentions an oscillator to produce tones at certain decibels. Is there anything else I could use? I can produce the correct tones but it's getting the correct levels I'm uncertain about. For example I have Cubase which has a master output meter. So I can set the correct DBu but then my soundcard output level would be different unless I calibrated that too. I'm guessing the phone apps to read decibel levels aren't the best either.
Calibrate test one is to input 1khz at 0DBu. Anyone know the best way to do that?
Thanks in advance.

[The Dude]

Do you have a scope? If you don't, I would leave things be, IMO. The existing factory adjustments are probably closer than you could get without proper and accurate measuring equipment. If you do start twiddling trim pots, mark their original position first so that you can put it back if things get worse.

[MarkusBass]

Yes, the preamp was (most probably) calibrated before it failed. Fixing power supply shouldn't affect it. I wouldn't try re-calibrating the preamp. If you have any other problems, they are most probably caused by some other failure (not yet fixed). Isn't the problem related to PHANTOM power supply for the microphone input?

Mark