Is there a door at the "door threshold"? And what is the subfloor, wood or concrete? Also, what is the w-2-w carpet material, wool or synthetic? Does it have antistatic threads woven into it? These are all important with respect to deleterious effects on signal transfer. You don't have to worry about the RGB, and if you're running speaker cable that far, I assume it isn't to your main speakers? The critical one is the Maestro IC.
My solution to this issue is to cut a strip out of the carpet right under the (closed) door and install a low profile (about 1" of space underneath) aluminum 'saddle' threshold in the space (about 3-5 inches wide depending on the extrusion you choose) running the cables under the threshold. HD carries them in natural, black/bronze, and gold. Pick the best match for your carpet. You can also have them custom anodized or powdercoated to match your carpet exactly, but that starts to cost.;-)
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My solution to this issue is to cut a strip out of the carpet right under the (closed) door and install a low profile (about 1" of space underneath) aluminum 'saddle' threshold in the space (about 3-5 inches wide depending on the extrusion you choose) running the cables under the threshold. HD carries them in natural, black/bronze, and gold. Pick the best match for your carpet. You can also have them custom anodized or powdercoated to match your carpet exactly, but that starts to cost.;-)
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