Atoll PR100 with Anthem MCA20


I bought an Atoll PR100 preamp recently and now have a minor issue with my amp. It seems that they are not a good match because I can't turn the volume up on the preamp much more than 2 even though it goes up to 10 because my amp gets too hot. Here are the main issues I see :

1) The preamp is very sensitive at 450 mV so it doesn't take much to get it to full power.
2) The preamp has a very flat impedance curve and lower impedance than my previous preamp, especially in the lower end of the frequency spectrum.
3) My amp has an input sensitivity of 1.2 V and an input impedance of 20KOhms.

So, I was wondering if anyone has tried the Atoll preamp + Anthem MCA20 combo before and whether they would be a good match. It seems so because the Anthem has an input sensitivity of 1.5V but it does have a low input impedance of 10KOhms.

Thanks in advance!