The bass from the "5" channels is ALWAYS redirected to the sub ".1" channel, no matter what position the switch on the back is in. This is the double bass thread discussed much here.
If the switch in the back is set to ON, there is no double bass. All bass (LFE and speakers below the crossover) is sent to the sub, but all the speakers are high passed too.
The double bass only occurs if you have the switch in the off position, then all the bass is sent to the mains *and* the sub.
SOP, go take a look at the link I provided. Explains (maybe not very well!
) the issue with the 950's digital and analog crossovers...