Audio Systems: Crackling or popping sound from preamp, crackling noise, internal circuitry

Question
I have a Audio Research LS26 that I have integrated with my multichannel theater processor.  When I use the processor bypass mode on the LS26 (hybrid preamp) I get an occassional ,which becomes more frequent, hissing, popping or crackling noise only through the right channel. I asumed that the bypass mode of the preamp would not be going through the  internal circuitry on the LS26 . I have eliminated the amps, Interconnects , speaker and the processor through a process of elimiation. I only get the noise when the preamp  is in the proccessor / bypass mode . I use this mode so I can use the sameL/R amps for my speakers when listening to music  or watching theater

Answer
If by process of elimination you have removed the multichannel processor completely, that is disconnect it from the LS26, and the bypass button does not produce any noises, then you have probably found the culprit. The bypass switch is nothing more than what it implies. When it's in the bypass mode it does not loop signal through an external device. When it is depressed the external device is inserted into the signal chain. If switching cable channels does not move the problem from right to left, then you have an intermittent condition with the processor and should have it serviced.