We had a discussion a couple months back, it is at the link below.

I finally got around to removing the offending driver, and I'm not 100% sure it is blown. With the driver out, I can make it make the buzzing type noise by covering the little screened port at the back of the driver. Is that normal for it to buzz when the port is covered? If not, then does that mean it is blown?

Fresno

• http://www.audioroundtable.com/PiSpeakers/messages/15087.html