I think he meant 9:00 or 10:00 o'clock. However, he should be able to turn the volume up on any Axiom DSP controlled sub to 1:00 or 2:00 o'clock with no issues. As long as he is not over-driving the input signal to the sub with his avr's sub level out, hopefully it's not at +5 or something...
I have my EP500 at 2:00 o'clock for months now without any pops whatsoever. Sub out level set to 0. FYI
M80's, QS8's, M22's, CHT SHO-10, Dual CHT SS-18.1's, Onkyo NR3008, Mitsubishi WD-73740