voltage fluctuations and surges can cause speaker pops which at times is also a clear symptom that the electrical wiring may be bad. I used to have a lot of popping sounds at random when I used to play my tapes and CDs. I ignored it till one day my amp literally exploded and fire was seen. Turns out that the phase and neutral were interchanged in my socket. PLUS there was a loose contact. The voltage surged due to the spark generated and burnt the entire circuit board.
Make sure to check your wiring and avoid ionization as far as possible.
Shankar
