Again, are you sure U1 feedback is implemented this way? It is connected wrong, should be along with the output.   Have a look at this: http://www.intersil.com/data/an/an1111.pdf

@XacTactX - I have already answered your questions in @ramachandra's thread. Also, you have 144 pages of useful advices in this thread. I've read them long time ago and suggest you to do so too.

U1 feedback point is wrong and non-inverting input is not referenced to ground :) Excluding these serious flaws, this is essentially a A47 amp.

You started a new thread without any need of it. It's the same mod, but you decided to show off yourself as the great copycat who even did things wrong. Sorry, wheel had been already invented.

Try NJM4556AD(D) OpAmp. 

OpAmp, output caps and C177 will do the most. Best output caps you can use - Elna Silmic II 22 uF/ 25V. Don't put any Low-ESR cap on C177, audiograde ones work best. Don't mess with the caps around the DAC (light blue ones on the first picture).   Be advised that the card uses big ground...

Last pictures are plain exmaples how NOT to do it. Sorry, but having so much stuff connected with wires in a PC case is rediculous. If you have ran a RMAA before and after the mod, you will know why. Also there is a reason some people suggest bypassing ratio to be around 1 to 100 at most ;)

Random loudness shift solved - I might need new speakers though.   Still cannot figure out how to make WASAPI/KS play stereo without tweaking the driver every time :(

Hello.   I have a X-Meridian 2G for couple of days and I notice some strange behaviour. I'm using Windows 7 64bit, Foobar 2000 1.1.10 with latest add-ons. Soundcard configuration is 6 CH input, 6CH output from the CMedia driver panel. Using 5.1 PC speakers.   Problem is:   - When...

Quote: What's the fun living then?  

Quote:   Thank you in advance for that :)   I should not be buying any new phones too ;(

Are you sure you have not something that is oscillating? Adding caps chaotically can create resonances.

Have you modded the STX somehow other than the XO?

Or your Vanguard was fake

Also have a look on Asus Xonar ST/STX. Headphone amp chip is TPA6120 = good thing. Dunno what the Headamp on Bravura is.