A thin layer of dust isn't a big deal, but if it builds up to more substantial levels, especially on the heat sinks, it will disrupt proper heat dissipation.
I found the problem. The cable leading to my PC had been eaten through by a mouse.... Looks like the cat dropped the ball. Replaced cable and sound has returned.
BTW, I share my bad luck with you so that you all don't go around thinking your lives are so bad.
I am very lucky many times over, I just like to make other people feel luckier.
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Creator of the Star Trek Mod - AST Mod - 78 Ship Sets - Conquest Mod - Atrocities Star Wars Mod - Galaxy Reborn Mod - and Subterfuge Mod.