Controlling audio when using 2 speaker systems

Ok, this might seem really strange, but what I have done is basically made a frankenstein speaker configuration.

I've got 2 pairs of speakers:

a) 2 speakers, 1 woofer
b) 2 speakers

I connected "a" to be the left and right port because speaker set "b" cannot distinguish between left and right sounds.

Therefore:

Speaker set "a" is connected to left and right audio jack.

Speaker set "b" is connected to the front audio jack.

From what I read, the M17x converts surround sound signals internally, would that thus give me surround sound?

Additionally, I want to specifically lower the volume of the front speakers (it has no external volume control since it's a >12 year old pair of speakers). IDT audio doesn't seem to have any feature to do that. Anyone knows of a solution to this?

Edit: Also, what kind of settings do I use on IDT Audio. Once I change both the audio jacks to Front and Center respectively, I only get sound from the front speakers.

 

Sorry to bump this post up, but has no one yet tried (or has the know how) as to how these audio jacks work? (As well as control the sound coming out from each jack individually)