Sorry for the late response, I flew from Phoenix to Richmond today via Charlotte. Long day.
8" speakers x 2.
The filter...interesting background...
I always used the cheapies and changed them at 30 days. Had a reminder set in my Outlook calendar and changed them religiously. About 2 weeks before I had the issue, I decided to buy the $7.00 Arm and Hammer filters. When this first started happening, I took them out and went back to the cheapies.