Funny story. When I got my Pioneer to replace an ancient Sony receiver which only had manual test tones, I figured since the Pioneer auto set the sub level, I'd just turn the sub up all the way and let the receiver cut it back as needed.
So the MCACC test begins. It plays a quick pink burst through each channel. When it gets to the sub, the thing makes a horrible sound and tries to crawl across the floor. The a message appears on the screen, something to the effect of, "please turn down the volume on the sub-woofer and try again."
I guess it was out of the ±10dB range.
At least it stopped me early instead of trying to continue through the test.
