Anyone with a Yamaha, Pro-01 mixer? Have "White Noise" Problem.

[kendall rownd]

Hello...
I have a Yamaha, Pro-01 Mixer, that has three channels that accept no input, but continually have a 'white noise" sound. The faders work...but the input attenuators / trim pots have no effect. For the rest it works perfectly.

Has anyone ever had this problem, and is so, do you know what / where the probem was? I have no schematics, but can walk around inside of electronics without stepping in something. I live in Europe and repair is difficult to find.

Thanks....Kendall

[crawdad]

I have one and do not have this problem. I have another one! In the hot summer months it makes intermittent loud buzzing noises, like it is short circuiting inside. When the weather cools down, its fine. Its not related to my house refridgerator, air conditioners or the temp of the studio. It seems to pick up the noise from the AC line itself. Wish I could offer more help.