I just recieved an 800RB that seems to have an exceptional amount of idling hum through the speakers (present with all controls turned completely down). I have been trying a couple of these lately- one from the same earlier era (late 80s) and one from the late 90s, both of which had some noticeable idling hum but neither seemed nearly as noisy as this one. There is also a pretty strong hiss with the Woofer Volume turned up to half or above, regardless of whether a cord is plugged in or input Volume is turned completely down. My question- is this to be expected from an 800RB from this era, or is this one in need of some work? (or maybe both...) I have played through a handful of these over the years, but this is the first time I have actually owned one and I want to make sure I'm not just crazy. I love the tone, but for the first time ever with an amp I find the noise nearly unbearable (I guess I've been lucky to have some pretty silent running amps- fan noise excepted- in the last several years). If it needed replacement filter caps, which seem to be the most likely source of the noise issues based on my quick internet research, how much might this job cost me? Are there any other obvious possiblities that might cause this extraneous noise? Thanks!