Amplifier Goes into Protect Mode Right Channel

Same amp, same channel again???? W two different phono stages and two different line stages??? I'd be thinking its something w the amp that only happens after it warms up, and that when you sent the amp back, the tech did not let it run for a long period of time. I'd try swapping speaker cables, then the various interconnects, and work my backwards to isolate the component. It'll be a long haul if it takes 1-3 hours each time to get it to go into protect mode, but that seems to be the only certain way.

Thanks for the recommendation. You're right, this is going to take an inordinate amount of time to isolate. I wonder if I should just contact CODA Technologies and cut to the chase and see what they say about the problem. I wonder if the right channel is going into thermal overload due to dust build-up or something like that. I could open it up and use a can of compressed air to clean it.

did you see leaking cap?

Hmm. For your solid state amp to go into protect mode, either it is itself broken or it is putting out a lot of power into the right channel.

Assuming the solid state amp is not broken, you should be hearing the power that it is putting out in the right channel unless that power is outside the audible range or outside your speaker's performance range. Unlikely that it is high frequency. More possible that is could be subsonic.

If so, it could be originating from your cartridge or turntable, although the turntable is less likely because it would probably affect both channels. Maybe your cartridge is going bad. How old is it?

Or it could be your phono preamp. Like something involved with RIAA equalization?

If your linestage preamp is working properly, it would transmit the subsonic signal to the solid state amp and cause it to shut down. If the linestage preamp is somehow handicapped from effective transmission of subsonic signal, then the solid state amp should keep working and not shut down.

Have you tried swapping left and right channels between the turntable and the phono preamp? How about between the phono preamp and the linestage preamp?

Probably the amp but to be sure switch the left and right speaker hook ups. If problem switches sides then switch the inputs to the amp. If problem stays in same side than it is in the amp.