I have a PreSonus HP4 headphones distribution unit driving two pairs
of my headphones (AKG K271 Studio and Grado SR80). As a headphone
amplifier, I would say the unit is very clean and good sounding.
However, the unit also has monitor level control to which I plan to
connect a pair of monitors. The problem is, when I measured the
monitor output of the unit using RightMark Audio Analyzer 5.3, I found
quite a level of stereo crosstalk. This is not the case for the
headphones outputs on this unit.

Another thing that concerns me is, the right channel is almost 1 dB
louder than the left, and the bleeding from right channel to left
channel is almost 10 dB higher than the opposite.

The measured figure is:
Left-Right @ 1kHz: -92 dB
Right-Left @ 1kHz: -84 dB
Left-Right @ 10kHz: -73 dB
Right-Left @ 10kHz: -64 dB

Is this level of crosstalk significant? Would the 1 dB difference in
level and the 10 dB difference in crosstalk, between the left and
right channels exhibit any audible effect from the monitors?

Please consider the problem both in general and in particular taken
into account that my listening room is very small and acoustically
untreated. Thank you very much in advance.

Poonna Yospanya