G3pb/sound Manager Hum Problems, noise and unstability Options

[jonbalke]

Gear:Powerbook G3. OS.9.2 / DP 3.17. motu 828.
Just spent a horrible day of error search.This is what happened: I connected my stuff in my home studio after travels, and switched everything on: loud hum and variuos noises.After checking all cables, I found the noise to be connected to input 1 and 2 on the 828.Later they occured on all inputs. So, thinking the firewire input on the 828 had been blown, I hooked up my Mac through sound manager and the small jacks on back, bypassing the 828 completely. Fine for a while, then to my horror the same sounds occur.Also , different digital-fax-like sounds when I pull the menus , open windows etc.
Now it seems like it has to do with to the back connector panel of the G3, like electricity leakage through the connectors. Or something.Any hints?

[divan]

hi

try to unplug the power-supply. if the noise is gone you know why. - hm, well at least mine makes the noises - its the little black one (my PB is quite ole). if you have allready the round, kind-of-transparent one... forget my words...

[jonbalke]

Thanks, but battery or power supply makes no difference. I actually had the transparent one, but had to change it for the rectangular black one. Anyway, after testing today it seems that input 1and 2 and 7 and 8 have hum/noise. 3/4 and 5/6 are OK. Why, I have no idea! Sound manager or Motu firewire driver makes no difference.
It might be electricity leaking in the back panel, but then why only on some inputs?Might this be the end of my good old G3?