I played CDs & FM stereo for about 2 hours. It performed without any problems, that is all the testing I did.  I used some Deoxit on the volume pot, thats all that was done inside. There is some corrosion around the vents on the right side. It is also on the inside and appears to have affected the metal on the coaxial antenna input (see pics). It doesn't look like anything else is effected, boards look ok. This was an estate buy so it has unknown history. Face is noice, case shows wear. In my experience Carver units haven't always been the most reliable & since this is a 30+ year old unit found at an estate sale it is sold "as is" That means no refunds or returns. Will be well packed and shipped Fedex in lower 48 states only. Look at the pictures and feel free to ask any questions.