3.5mm to RCA cable suggestions.

The specs on page 7 of this manual for the Little Dot MkII indicate an impedance for its RCA outputs of 600 ohms, with no indication of the frequency on which that is based. Most likely it is based on a mid-range frequency such as 1 kHz, and I wouldn’t be surprised if the impedance at deep bass frequencies rose to amounts that are much higher than 600 ohms, and that are too high to be optimal in conjunction with a 10K load. Although the MR8 can’t reproduce much of the bottom octave (20 Hz to 40 Hz) anyway, so the impedance issue might not be noticeable even if present. If it were me, though, I wouldn’t purchase the Little Dot unless it could be returned without a restocking fee or other penalty.

Good luck, however you decide to proceed. Regards,
-- Al

" I am probably mistaken, but I though there was a problem going from unbalanced to balanced without proper grounding."

You have it right. That's why you can't run a component balanced and SE at the same time. That's why most fully balanced components have either a switch, or jumpers you insert in the xlr jacks directly to run in SE mode. 

Regarding proper grounding, I would expect that a stereo 3.5 mm to dual XLR adapter cable, such as the Hosa cable the OP linked to earlier, would accomplish that. Presumably it connects the ground of the 3.5 mm plug (the "S" of its TRS connections) to pins 1 and 3 of both XLR connectors. Pin 1 is the ground connection of an XLR input, and pin 3 is the signal pin that should be grounded when an XLR input is provided with an unbalanced signal.

The cable presumably also connects the "T" (tip) of the 3.5 mm plug, which conducts the left channel signal, to pin 2 of the XLR connector that would be connected to the left channel speaker. And it presumably connects the "R" (ring) of the 3.5 mm plug, which conducts the right channel signal, to pin 2 of the XLR connector that would be connected to the right channel speaker.

That would all function in a reasonable manner. However, for the reasons I stated earlier connecting via RCA would most likely be preferable.

Regards,
-- Al

Here is the 3.5mm/TRS also:
http://www.musiciansfriend.com/accessories/kirlin-original-y-cable-3.5mm-trs-plug--2-x-1-4-in.-mono-...

The same comments I had about XLR vs. RCA apply to the Kirlin 3.5 mm to dual TS (not TRS) cable linked to above, vs. RCA. Also, I’ve never liked 1/4 inch connectors because in my experience the contact they make can sometimes become intermittent, especially if they happen to be jiggled.

Regards,
-- Al