I have an Asus Xonar DX audio card. I read in multiple threads that many users have issues with this card not working or system (with this card) not booting with newer BIOS'es with this mobo. Also, I don't like the fact that you can't simply flash back to an older BIOS in case of trouble. This is why I'm not updating. Also, EVERYTHING works fine now and system is 100% rock stable and also ram is overclocked.
In your case I would stay on which ever bios you are on then.
I have no issues with my X-FI Titanium audio card in my build, for me this is probably the best bios i've has on this board since purchase.
The only issue i've had with previous bios on this board was with 1405,1407 after flashing those my system wouldn't go past the Bios Splash after the flash with my Raid 0 drives plugged in. I had to unplug them boot up then restarted and plug them back in.
On this newest bios that is no longer an issue for me.