I decided to drill 1/8 inch holes in the back rather than the side. It improved the time for the popping to occur from about 20 minutes to an hour. I put 22 holes on top and another 22 on the lower part of the back. It did effect the sound quality some but it’s better than listening to the popping . I intend to drill more holes, not sure where right now. Will drill one larger hole and look inside to determine where.
I have the popping problem that a lot folks have complained about when the unit gets hot. I’m willing to try to drill holes on both side on top and bottom to create air flow to reduce the heat and possibly stop the popping. Any one have any thoughts?