Yeah, that's quite typical. When I re-wired all my sound system, I had made the correct measurements for everything. But then I moved the pre/pro by 8 feet... and just went "bah! I so overcompensated for future proofing, no need to recalculate". Well, I was missing 3 inches for the subwoofer (25 feet cable) and 3 feet for my backroom (50 feet cables).
But thanks to an excruciatingly long back order on the device, I managed to get my new monoprice order in time!
E = MC2 = ((2M80 + VP180 + 4QS8)/(EP800 + EP500))^(ADA1500 x D2v)