On some of these Jensen AV units, the "A" speakers are a set of four, the fade takes them between front and back pair. The "B" and "C" speakers are a second set of four, the "B" set is fade front and the "C" set is fade rear
That said, have seen a number of them wired with "A" Front and "B" Front as the four inside speakers and "C" Rear as the outside speakers.
Probably depends on who was installing that day, as well ....
Jeff and Abby
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