I bought an Insignia is-hc040918 stereo receiver (200W) from a pawn shop and it was in perfect working order for about 4 months. Then after Christmas break it began putting out a scratchy static-y sound ONLY from the left channel. It usually takes about 10 or 15 minutes before it starts to do this, so my obvious guess is when something heats up enough it starts to exhibit this behavior. It will do it at about a constant volume regardless of whether there is any sound coming from the speakers or how loud the sound is from the speakers, so long as the unit is turned on. I'm an Electrical Engineering student so I have a basic understanding of circuits and am experienced in soldering. I've taken it apart once to look for any clearly damaged components but everything inside looks perfect. Thanks for any help you can offer...I'm hoping it's just a blown component that can be replaced, again thanks anyone.