I have just finished getting a stand made for my kit and am now trying to get it set up using the computer. Up to this point it was set up as a 5.1 system - DSP33/5000C fronts and analogue rears with a single D1500 running off the centre and worked fine. I have now attempted to reconfigure the system with stereo subs - and have wound up with none! The remaining speakers are working ok. The cabling is as follows:

568->centre Signal (3/4) & comms (master) to signal/comms inputs.
centre->511 Comms only.

568->front left Signal (1/2), comms from 511 to signal/comms inputs.
F left->F right Signal & comms outputs to signal & comms inputs.

568->Rears Rear analogue outs.

568->Right sub Signal (5/6), comms from 511 to signal input & inner comms socket.

Right sub->Left sub Signal out & outer comms to signal in & inner comms.

The settings on the left sub are: 1, flat, maximum gain.
The settings on the right sub are: 2, flat, maximum gain.

In the congfig programme layout the:
Fronts are 96/24 DSP small
Rears are large analogue
Subs two - left/right for music, logic & 5.1 movie.

In sizes the fronts aren't highlighted with max ticked, the subs are narrow, DSP with the level at 30 (although I had ticked max), rears are set to 17 with max spl at 109. The crossovers are set to 80 for music, logic & 5.1. Music LFE is off, 5.1LFE is 120. Phase/gain are all positive/0.

Connections agree with what I have detailed above.

When I did the initial setup (expertly assisted by Mr Meridian) I seem to recall typing the 568 as 5.1DDA, looking through the manual (p68) I can't see a type for multiple subs, so I have left it alone.

Can anyone shed any light on why I have no working subs?

They both worked as singles in the old 5.1 system & the leads were ok as well.
Sorry for the essay - but I would imagine I have made a 'schoolboy error' somewhere & thought it best to include all the information.

568.2mm, DSP6000, DSP5200HC, DSP33 rears, HD621, LG G3, Sony UBPX800-M2, F80.