Noisy mixer channel.

If you have changed all the caps, transistors and op amps I would think that it should be reasonably straightforward as it must be with one of the few remaining parts.
If it were me I would run the channel and check if the noise is controlled or altered by any of the controls (zb if it goes up and down with the input gain then it is clearly upstream from that control, so just a handful of parts, A bit too obvious I know, but if it is affected by the mid sweep but not by the treble then you are getting close or if none affect the noise then look at the pfl circuit, if no noise there.. well you get the idea) There was a common problem on some of the older, large format Yamaha desks that would whistle quietly to themselves, that was one of the multiway pots, not that I'm saying change all the pots but in this case it was located by simply swinging the pots until one was located that had an effect.

The supply to the phantom power is upstream from the gain somewhere near there, not quite sure what would happen if the strip was fed by one legged phantom? does switching the 48v on make any change? (ie 2 legged)

Solve the problem!! It was a smal glass 1N4148 diode coupled to the op amp! By messuring it was looking good, but I've replaced it with a new one and the noise is gone now.  

Edited by JR.junior - 25 January 2012 at 9:08am

I think this might have just helped me out infact.. Studiomaster 16-2 diamond club desk, channel 15 has white noise and interference on R side.. I'm intrigued now to see what's happening on this board