Thanks, all of you, for the information about the impedance switch. That being in the low setting, and having my fronts -- the M80s -- set to large, may very well be what has sent my Onkyo 3008 into protection mode. Also, I'm using the setting that sends LFE to the large speakers, as well as the subwoofers, so that could also be a factor.
In the discussion thread at Audioholics, there is some dissent from user kaiser_soze that the high impedance setting really is best. I'm looking forward to seeing some test results for this specific receiver about its behavior with 4 ohm speakers at the two impedance settings.
I have my fronts set to large, because my EP500 is using its high level inputs connected the receivers front outputs. The reason for that, in turn, is that the EP500 line-level inputs don't work. (It's obvious that there is a possibility of getting this repaired, so you needn't point it out to me.)
I'm still interested in the answer to the question I asked, if any of you has relevant experience: Would the XPA-3 used for the M80s (and VP180) fix the protection mode problem? I know there might be other remedies, but would the XPA-3 work?
