ARC MCP33 pre-preamp - hiss in one channel - Gofast

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ARC MCP33 pre-preamp - hiss in one channel

Hi guys. I just finished rebuilding the power supply sections in my ARC MCP33 pre-preamp - replaced the toroid (which had burned out), diodes with Schottskys, new voltage regulators, and all the electrolytic caps. I also replaced the 12at7 tube, all the other tubes (1 7044 & 3 6DJ8) measure marginal to good on a TV7.
Its now working, and opening up a little as it burns in. I had it playing for 3 hours last night. However, I experienced 2 problems with it - hoping the experts here may be able to shed some light on it.
The left channel is MUCH noisier than the right - higher level of hiss. I tried moving all the 6DJ8s around, to no avail. So guessing the problem is somewhere else? I've not checked/changed anything after the power supply.
Can resistors go bad and cause this noise? How about the other types of caps? Do polyprops go bad? Seems unlikely a film cap would have gone.
- Initially when I started it, I played 1 LP, then I realised it needed to burn in, so I swapped out the tubes as well to the new 6922 tubes I had bought - figured they could burn in together. And, after about 5 mins, the fuse popped. So I put the original 6DJ8 tubes (and a new fuse) back in, and it ran for about 3 hours last night till I shut down.
The schematics are on arcdb.ws
I'm very happy I brought this ebay disaster back from the dead (it was not disclosed that it did not power up). And the quietness of the right channel gives me hope..
Any thoughts on what I should do next? Thanks, Samir.

MCP33 schematics on this page (Open in New Window)

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Topic - ARC MCP33 pre-preamp - hiss in one channel - Gofast 05:30:49 11/13/06 (4)

Re: ARC MCP33 pre-preamp - hiss in one channel - BBeck 07:37:45 11/13/06 (3)

Re: ARC MCP33 pre-preamp - hiss in one channel - Gofast 09:45:33 11/13/06 (2)

Re: ARC MCP33 pre-preamp - hiss in one channel - BBeck 15:37:32 11/13/06 (1)

Re: ARC MCP33 pre-preamp - hiss in one channel - Gofast 19:53:34 11/14/06 (0)

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