the speaker on my iHome is squealing. MAKE IT STOP!?

I recently acquired an ihome from a friend. the reason he gave it to me (like so many others) is because I am fairly handy and people know I can fix stuff, and this particular device emitted an irritating squeal. when you turn it on, it has a (fairly loud) high-pitched squeal that sounds not unlike a simple square wave. it doesn't really fluctuate, it just squeals. it doesn't go away when the volume goes down, and when you play music it seems to intensify. does anyone know what could be causing this, and how I could get it to go away? (if all else fails I might try adding an inductor to block the high frequencies.)

framistan4 years ago
I would open it up and look for an electrolytic capacitor that feels loose when you wiggle it GENTLY... or inspect under the circuit board for cold solder joints. If you turn the unit on while it is disassembled, you can use a plastic ink pen (so you don't get shocked)... to gently wiggle parts on the board. If you touch the BADLY SOLDERED or LOOSELY CONNECTED part... the squeal will suddenly stop, or get worse for a second... that is the part likely that needs to be re soldered. UNPLUG the IHOME before soldering on it.

iirc they're all low voltage (or at least the ones I had were) but good advice on the safety for all electronics. It's probably the smps input conditioning circuit.
codongolev (author)  framistan4 years ago
thanks for the info. this is probably it, because (as I forgot to mention) the squealing WAS rather intermittent and staticky until I wiggled the power cord, then it became smooth. so that's probably the issue. I'm going home from college tomorrow and I'll let you know how it goes.