Turntable problem

I have a Denon turntable DP62L with a AT 120E cartridge.(It was just serviced and a new needle installed) When I hooked it up to my older Sansui AU717 amp it works fine no problems, but when I hook up the turntable to my new amp a Sansui AU X707DR, it does not work right the sound starts to cut out if you turn up volume, if I turn on the "subsonic" filter on new amp it will go a little higher in volume but it will still start to cut out (I do not listen to music "real" loud, but I can't get it turned up to normal listening level).
The new amp only has one location for phono jacks and in front there is a MM/MC button "in" engages MM "out" engages MC. (Volume cuts out on either setting and the sound is muffled on MC setting)

Do you have any ideas what the problem might be and how to solve it?
Is the AT 120E a moving magnet cartridge? I do not know, the cartridge came with turntable when I bought it. I did have the stylus replaced recently with a "diamond needle *208-DE replaces ATN-120E". If the AT 120E is not a MM/MC would that be a problem since the new amp only has MM/MC settings.

The new amp works fine with tuner and CD just trouble with turntable.

Thank you
I would say if you could replace the stylus it is a MM cartridge. The muffled on the MC setting confirms it.
Try using a standard aux input. The phono stage in you unit sounds like it is not matching up with the cart output.
The AT 120E is, indeed, a moving magnet cartridge.

For some reason, I think some Denon turntables use a built in phono section. The output from such a section should be connected to a line level connection (like a CD player or tape deck.) Of course, there could also be a problem in the amp.