Waldorf Blofeld noise/buzz??

[Burial_Grid]

Hey hi hello. Picked up a Blofeld a few weeks ago and was disappointed to find that it's absurdly noisy. There's a high frequency buzz that's quite audible through the phone jack and the output. It stays consistent regardless of the volume knob's position. I've tried multiple power adapters. Used it in various rooms, which rules out interference. I've tried it with and without MIDI and USB cables plugged in. Do I have a dud of a unit or is it really just this noisy? I'd rather not lose all those rich harmonics by notching the frequency of the buzzing out.

Thanks!!

[Rasputin]

I've tried multiple power adapters. Used it in various rooms, which rules out interference. I've tried it with and without MIDI and USB cables plugged in.

Totally generic and non-specific to Blofeld idea:

Bad (cracked / cold solder) joint on the ground lead of the power input.