Change Interconects? Will it Help?

Hard to say if it will or not. You could try changing out the front channels and see if it changes anything....the back speakers are only for sound effects, so would leave those alone ( but that is just my .02)

What change or improvement are you looking for? For what it is worth I had the same monster cables and when I switched to the Audioquest King Cobra's there was quite a difference (for the better). A little more forward all around. Better bass mids and highs. Then I upgraded to the Fusion Audio Interlocker II's. Again forward - more from top to bottom and a larger sound stage than the King Cobra's.

Also as stated start with the front pair first. Decide from there if its worth it.

IMO your biggest bang for buck will come from upgrading the pc on that 805. ICs will help too though on the BJ level not as much.

That's what I've found out on my own 805 + Butler 5150, using Audio Art cables, Micro Pearls, and even a pair of MIT Shotgun S2. The power cord made lots bigger diffs than the ICs, and rather set the table for them by adding or allowing more bass response, detail, and a more enveloping staging or presentation.

Don't they have a return if not happy thingy at Blue Jeans? I think so if it's not a special configuration. They're nice people so just ask & see.