Their should never be a 'pop' through your speakers. Your hearing a transient signal that is potentially damaging to your speakers. Always be sure upon system start-up that all your volume levels are down. Your preamp (or receiver) goes on first, also your input components (i.e. dvd, tuner, cd, etc.). Turn your amplifier on last. Then turn your volume up. If your amp or receiver has an on/off switch for your speakers, then turn everything else on, and switch on your speakers last. Reverse the above order for system shut-down.
The clicking noises that you are hearing at the amp or preamp are start-up relays closing. No problem there.
A 'pop' is not supposed to be there. It's just improper start-up procedure.
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