Faint click from speakers

Hey Folks - was hoping someone here could help me out. I recently put together a system in a new house that consists of a pair of ProAc D38s driven by Cary 805Cs and a Cary 98p.

Everything sounds great except sometimes I hear very feint clicking or popping sounds from both speakers. The clicks usually start up after the system has been playing for a few hours and fully warmed up. Then the brief clicks start and continue every 4-6s coming from both speakers. They sound like the pop from dust on an analog record but very feint, and they do not get louder when I adjust the volume on the preamp. I've tried shutting off the preamp and sources, but the clicking continues. I've also put the amps into standby mode and that doesn't help either.

It seems like the source of the clicks could be the power from the wall outlets. I have everything connected to a PS Audio quintet, and I don't have any other power regulator/conditioner along the circuit.

Any ideas? Thanks in advance.
Had something similar. Only with my monoblocks it happened with only one speaker. The culprit was a capacitor in one of the amps. It initially took hours for it to occur but over time it increased till I couldn't turn on the amp without the sound. Since you have it in both it could be the same cause but perhaps in the preamp or just bad luck to have the same cap go out in both amps, a very unlikely possibility, but still one none the less. Hope this gives you a start.
If the clicks only start after the system has been playing a few hours, my guess is that there is a bad part somewhere. I had something similar and it turned out to be a bad tube in my pre. OTOH, maybe its something getting ready to fail in your PS Audio. I guess what I am saying is that I think there may be a part (be it tube, diode, capacitor, resistor, solder joint, whatever) that gets thermally stressed after a while and that is what you may be hearing.
You might try plugging direct into the wall and bypassing the Quintet. You say it is a new house so try another outlet on a different circuit. Could be a grounding issue or rfi/emi issue on a particular circuit that is shared with dimmer or similar. If no change then as mentioned it may be an equipment issue, try the cheapest first.
My best guess is a bad paper and oil capacitor,I believe Cary may have used them in their products,one or more be leaking DC.I had this issue with a PIO cap in my home built Hagerman gear,I replaced them all with Film and Foil's and this seemed to fix the popping sound I was hearing thru the speakers.
I would contact the dealer/manufacturer and pick their brain.
These are some great suggestions. It's been so hectic with the move and at work that I haven't had time to do a lot of troubleshooting. Tricky part is that sometimes it takes hours for the clicking to start up.

I'm hoping that the Quintet is culprit, as it would be the cheapest fix! It better not be the amplifiers because they weigh so darn much that I would hate to be forced ship them anywhere! I'll let you guys know what I find out.
I just had the same problem, it sounded like a TT was going around and the needle just keep going pop, then a few seconds later pop, etc. It turned out to be a tube. So check those first.

Happy Listening.
Well, I think I managed to isolate the problem to one amplifier, the left monoblock. After the amps are warmed up, I can hear the clicking in the left speaker, even when the left amp is in standby mode. Interestingly, when the right amplifier is on and in listen mode, I can also hear the clicking in the right speaker as well. Putting the right amp in standby eliminates the noise in the right speaker for some reason. Turning off the left amp and waiting for the power to drain out eliminates the clicking from either speakers.

I tried to swap tubes, power cords, and fuses from the left and right amps and still hear the noise when the left amp is powered on. I'll try contacting Cary next week to see if they have any ideas.