How can I use headphones and speakers at the same time with no front audio port?

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How to get headphones and speakers working at the same time?

I want to use speakers and headphones at the same time to output sound, even if I have to change some setting to switch between the two.

I have an ASUS M4A79XTD EVO motherboard, which, according to PC Wizard, has "ASUSTeK Computer SB600 High Definition Audio Controller" for the onboard sound card. Newegg says it has a VIA VT1708S chipset. The sound card has 6 ports on the back, and supports up to 8 channel audio. The drivers themselves use an application called "HD Audio Deck", which is very frustrating to use. I currently use 32-bit Windows XP.

What I would really like to do is use both the standard output, and one of the other ports to output at the same time. In the software, the closest thing I can get to this is either set it so that headphones(the non-existent front port) and the one of the back ports, or increase it from 2 channel audio to 4 channel, which is surround sound.

Is there, by some setting I've yet to discover, or with some other audio controlling software, control the exact streams of audio and route them to which port I choose? Maybe not even something this fancy, perhaps just forcing or tricking the drivers or hardware to output the same audio on several channels, without processing it to surround sound?

I am aware that I could craft or purchase a headphone splitter, which would solve all my problems, however, I'm wanting too try to fix this with just software.

If I've not been clear in any way, just ask for clarification, I'll do my best to clear it up.