1) I recently replaced the surrounds on the PR15Cs from my L222s. Now there is a very annoying buzz emanating from each of them during deep and sustained bass frequencies, the kind that are common on DVDs. The volume doesn't have to be very load to hear it. When driven by an audio signal generator, the noise occurs from about 65 Hz to below 20 Hz.

I used a surround kit from Orange County Speaker and the whole job was easy and straight-forward. The only difference that I noticed between the original surrounds and the replacements was the width of the rolled edge. The original rolled edge fit snugly against the inner edge of the gasket, whereas the new edge falls short of the gasket by about a 1/16".

I've inspected the speakers and can't find any obvious reason for the noise. The surrounds are glued tightly against the cone and appear to be tight against the surface of the basket. The spiders appear to be tight and in good condition.

I’ve noticed that the surrounds even make a noise when I push on the cones with my fingers. It's kind of like the "scratching" sound that foam plastic makes when handled.

Has anyone else encountered this problem, or does anyone have a suggestion for solving it?

2) I’ve thought about replacing the PR15Cs with a port. It would be easy to fabricate a blank to fill the hole occupied by the speaker and put a port in the middle of it. However, I'm not sure how this would affect the sound and I'd need help to properly size it. Does this idea have any merit?

Thanks,

John