A small additional point, Noloft.

Before you hit 6CH, be sure you're in a multi-channel processing mode e.g. Dolby DD/Dolby PL2, DTS, or Stereo 5/7. If you are in a two-channel mode, such as Stereo, the 950 will only activate two of the six analog channels.

It's an eccentricity of the circuit design, apparently.