Volume on my Pathos Classic One MKII ????

I just purchased a lightly used Pathos Classic One MKII. I have to turn it all the way to 80 or more to get a realistic listening level. That's really driving it to it's max which I believe is 100 on the volume readout. I use a pair of original Audio Physic Virgos with a Basis Signature 1400, Shelter 501 MKII and a Pro-Ject Tube Box.. It sounds like the speaker is really working hard here. Any insight or thoughts on this would be greatly appreciated.
Could your TuneBox may need more gain...Is there a gain switch (MM/MC), and if so, is it correctly positioned for the Shelter? Have you tried a line input with your Pathos? Plug in a CD player to see if there is a similar problem there. If you don't have a CD player try the audio outputs on your DVD player or any line-output. At 88.5 db efficiency your Virgo's should not present too much of a challenge to the 70 watt integrated, but a larger listening room may add to that challenge. Still, it shouldn't be that far off as you describe.

Is there a 20 dB mute or similar that might be engaged?
I am playing a cd and its the same. How does this unit switch to a 4ohm load? The Virgos are rated for 4ohms and the Classic has that option. My Primaluna intergrated had separate speaker terminals for this.
In many cases (virtually all ss amps) there is only one set of speaker taps. I repeat, is there some kind of mute function?
Swampwalker - there is a muting switch on the remote for the Mk ii version, so Dreadhead, you should check that and let us know if it may be engaged. Per Swampwalker - your Hybrid amp, deals with the different loads internally, and not via variable connections as tube amps use. Are you sure you have a Mk. II version...the earlier version only puts out 50wpc, which, again, may be too low a power rating for those speakers. I did a quick search on what amps folks are using with Virgos and it seems like most are using high-current, high wattage SS amps with 100 wpc being the cutoff (though I did notice one guy trying out a low-powered push/pull tube amp with what he thought were good results. Are the correct tubes installed in the pre section? One unlikely scenario... could the previous owner have replaced the proper tubes with some other 9-pin alternative variation?