I replaced my head unit yesterday (non-HK) after having issues with it turning on even when the car was off and draining my battery. I bought another stock head unit off eBay, from a guy also on the NAM boards. The replacement install went really easy, but when I was listening to it on my way into work today I get a squealing noise from the front speakers, instead of any bass. The rear speakers are fine, but the front just squeal away. This happens with both the CD and the radio.

Anyone have any input on this?

Thanks in advance.