^ Sure there is. Leave them enabled and they are not down-mixed.
For example, wire LF/RF only from the multi-channel Analog set. Then in Speaker Configuration, set Down-mix to 7.1. Then in Speaker Configuration, set Subwoofer and Center to OFF. Set LF/RF, and all 4 Surrounds to LARGE.
Any Center or LFE (i.e., Sub channel) content in what you play will be down-mixed into LF/RF. Any Surround channel content in what you play will go out the 4 Surround jacks. If you want to DISCARD that SURROUND content, simply don't wire those 4 jacks. If you want to hear it, then wire to your 4 Surround speakers.
Note that you will have about -15dB "down-mix attenuation" as the player needs to establish headroom on the LF/RF jacks for their combo of output. Raise volume in your Pre-amp to compensate. You should experiment with setting Subwoofer to ON (even though not wired) to discard any LFE channel content. That will significantly reduce the required attenuation and you may like the result better.
If you add a Center speaker as well, just change it from OFF to LARGE.
NOTE: If your intent is to use the Analog outputs as your primary audio, then you should look at the 105D, as it has a more exotic Analog audio output solution.
NOTE 2: Down-mixing can not happen if you are using DSD-Direct-to-Analog Conversion, as when playing SACD discs. So set SACD Output = PCM to avoid that.
Last edited by Bob Pariseau; 06-12-2014 at 07:39 AM.