Anything to be gained by using Jack to XLR outputs?

[JIT]

Would i be better connecting my active monitors using the Jack to XRL outs on my M-Box or would jack adaptors on a RCA to RCA cable be just as good?

It would be around 1 metre in length or so.

[JCBigler]

By "jack", do you mean the 1/4" TRS connections? Yes, a much better option than the RCA. The 1/4" TRS output jack are already balanced, and only need to be plugged into the XLR inputs on your monitors. The RCA outputs are unbalanced, and are much flimsier than the 1/4" TRS jacks.

[JIT]

Yes, TRS to XLR.

I don't think the M-Box has balanced outs though so would this still be a better option than using RCA to RCA with TRS adaptors?

[rqstudio]

Originally Posted by JIT

Yes, TRS to XLR.

I don't think the M-Box has balanced outs though so would this still be a better option than using RCA to RCA with TRS adaptors?

If the MBox has two TRS outs then yes, they are balanced and yes, it would be better to use them. You will experience less hum and better imaging. Also you should never run an audio cable parallel to an AC cable or bundle them together. And you should try to keep them as short as possible.

[JCBigler]

Originally Posted by JIT

I don't think the M-Box has balanced outs

Yes it does.