Help with Gain Structure - Mcintosh D100 pre to Primaluna dialogue HP amp

Trying to figure out how to set the appropriate gain for the system;

Using the Mcintosh D100 (Dac/preamp) as a preamp going unbalanced into the Primaluna Dialogue Premium HP amp.

D100 - 0-8 Vrms output sensitivity (I think that's around 26dbu  gain)
Primaluna - 1.1 V input sensitivity.

Sound quality is really amazing so I'd like to make these components work together (vs selling/buying more closely matched components.)

Using Tidal through Heos Link (Denon) Toslink/optical output to optical input in D100.

The Heos has a variable level out (through the app.)

Sound quality wise, if I limit the Heos variable out (say to 60%) so I can get more range in the D100 volume control without clipping/overdriving amp, will I lose quality, headroom, dynamic range, etc?  Problem w/this might be that if by accident the volume gets turned up it'd be an issue.

Would it be preferable to attenuate the output of the D100 going in to the Primaluna (rca 10db pads, etc?)  Seems the best way to go, any suggestions on pads, etc?

thank you