You can get a can of air at Radioshack and clean up the interior of any dusty receivers and try them again. However, Mikec is probably right. While dust isn't helping, the power may be the biggest problem. Another option would be a Tripplite surge supressor and voltage regulator--it might cost more than the receiver, but could be cheaper than a dedicated line. In the long run, its got to be cheaper than replacing receivers regularly.
Electronics in Dusty Environments
I love to listen to music including in my workshop. I have a pair of outdoor speakers power by an older reveiver & listen to FM only. My problem is the receivers keep craping out...I believe due to excess dust. The last 2 receiver lost most of the left channel. My question is, Can these receivers be easily fixed by myself? It would seem the problem would be minor. How would you go about fixing them. My thoughts are to blow the the insides out with air & is there some kind of cleaner to spray? Where would you spray it? Please be specific as I never done this before. Thanks in advance. P.S I've moved the electronics out of thw workshop to avoid dust in the future.