Use Google for your search.
Two examples, just as it is written without spaces around plus sign...
dirty switches+audiokarma
Marantz+audiokarma
If you want to search a particular site, use the + symbol with no spaces around it. Google uses Boolean operators in it's search function. Use model numbers for more specific answers. You can also create a free account at HiFi Engine to access a library of Owner and Service manuals.
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