windows to hdmi to optical no surround option

[Fullbasher]

So basically ive been going all over the internet and cant find a solution to this. basically i have an hdmi out from my windows 8 computer to a passthrough/converter box which then goes to a mixer where audio is upconverted from 5.1 to 7.1 and goes to my headset. my problem is i need to force the computer to outputting 5.1 through the hdmi and i dont know how.

 

[shaqblogs2011]

You are chasing ghosts. You are playing multichannel using headphones which is essentially 2 channel.

 

[ssddx]

there are far simpler ways to get what you want.

if you're using a stereo headset and want 7.1 then just use virtual surround from a soundcard. dolby headphone or cmss3d/sbx would work fine.

if you're using a true 5.1 or 7.1 headset with the appropriate multiple 3.5mm plugs then using a soundcard with 5.1/7.1 capability is also the best solution.

why doesnt your hdmi->optical->mixer->headphones work? likely because your pc is not recognizing the destination as a 5.1 capable device. as far as forcing the output to 5.1 if the option is greyed out? besides writing custom drivers or using modified drivers someone else made.. i would say no. you could try to shorten the chain of devices to see which is causing the issue with your pc but other than that i dont think theres a fix.