Need to figure out how to troubleshoot

I KJ with 2 Peavey SP15 speakers on a 1600w Peavey amp. I am getting intermittent popping in sound and not sure exactly what is causing it. I thought it was coming from cheap mics but got different ones and still have the problem. Besides putting on varying tunes, with no mics, for an extended period of time, to monitor if I experience any bad sounds, is there a way to test the speakers on a more technical level? The speakers sound great otherwise and I have been using them for a number of years.