OK, I see the info there.  What cards are in which slots?

Alright, I will get this passed on

EVGATech_DaveB
Hello all, I have passed all of the info provided to me via posts here, PMs and emails, including the BIOS's.  The engineering team has purchased your models of ASUS sound cards and are unable to replicate it, infact to verify it they sent me a video of it working and it works as intended.  Which as I told them, the community is obviously having issues still, the thought our engineers have is this, there may have been a hardware revision on the cards, as most people who have card issues have had these issues for a while. 
Now I am not personally familiar with all of the minutia of ASUS sound cards, however with most components there are some type of BIOS/Firmware revisions silk screened onto the device as well as PCB revision.  We might have different revisions, we are thinking ASUS did a rolling update on the cards.  Would it be possible to get some high resolution pics of the cards front and back, fro all of you who are having card issues, and send them to me here
I will pass that to the engineers and see if that is our problem.

1) Which exact motherboard?   Part number or product name is fine either way, we don't have THAT many X99's
EVGA X99 Classified Rev 1.00
2)  Motherboard BIOS revision
1.19
3)  CPU and memory, for the memory please supply a full part number, or even the link you purchased it from.
CPU: Intel I7 5930K
RAM: G.SKILL Ripjaws 4 Series 8GB (2 x 4GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000) Intel X99 Platform Extreme Performance Memory Model F4-3000C15D-8GRK
4)  FULL component config, what devices are plugged in and to what slots
PCIE 1 EVGA 780 TI SC
PCIE 2-3 empty
PCIE 4 EVGA 780 TI SC
PCIE 5 empty, but used by M.2 SSD
PCIE 6 ASUS Xonar DX
5)  Exact model of the sound card, as there are a few Xonar's. 
ASUS Xonar DX
6)  Sound card driver version, preferably also a link to the specific download you are using.
ASUSTek 8.1.8.1823 C-Media Electronics Inc. Link: 
7)  OS, and is it updated?  If you are bypassing any updates, please provide the KB number.
updates are automatic, and was forced yesterday dec 15th 2015, Windows 10 X64 and for what i could find, the kernal is 10.0.10586.17
8)  Please go into your BIOS and save a profile of your BIOS, and send it to me at 
sent after this posting, since i have to shutdown to take the card out and take pictures of the card as well

EVGATech_DaveB
Hellbeast,
I forwarded this info onto the engineers.  Thanks for getting it to me.

you are very welcome, i hope this gets fixed soon

Kutz_HGZ
Hello everyone and happy new year !
 
Last mounth I updated to Bios 1.18 on my X99 FTW card and I have still the issue.
Any update from de devs ?
 

i suppose you could submit the same for that the rest of us have so that  could send it to engineering as i did in a previous post

Is any updates about Xonar problem . i am waiting from 11/24/2014 . LOL 

EVGATech_DaveB
Hello all, I just posted new BIOS for the 4 X99's, they have fixed more of the Xonar issues as well as added in Secure Boot.
 
Part of the issue with the Xonars has been there are a bunch of different revisions and need slightly different things for fixes.  Please download and give it a shot, I have a sticky for the new BIOS as well as have the BIOS's available in the regular download location in our support section.
 
Please pass along any feedback you have on this release.

So far 1.20 is working perfectly on my X99 Classified, thanks for the update and hard work, i finally do not have to restart to use my xonar sound card!
 
thanks again,
hellbeast

Hello !
 
I came back to this post to update my Sonar DX issue.
I just installed the latest Bios 2.01 on my X99 FTW card and everything is working !
PCIe setting Auto, Gen1, Gen2, Gen3 The card works like a charm at cold boot !
 
Many thanks EVGA for this fix, you are awesome !!!! =)