You could try expanding the System with this card, FL1100 chipset is supported nicely by the MADIface driver / UFX+.

I would recommend getting the PRO model, which is equipped with 4 FL1100 USB3 chips, so that each of the 4 ports has an dedicated USB3 controller, by this you
- fully isolate the UFX+ behind one USB3 port
- have still 3 other USB3 ports at full USB3 speed
For me it worked phantastic to i.e. connect two UFX+ and one ADI-2 Pro.
It requires a x4 socket because of this throughput, you could i.e. use the 2nd GPU PCIe socket,
as your system seems to support x16/x16, so that your primary GPU doesn't become slowed down.
http://www.sonnettech.com/de/product/al … 3pcie.html

This is the cheaper card where one FL1100 USB3 controller is shared by the 4 ports which I do not regard as very useful.
Especially as you do not have that many PCIe sockets.
http://www.sonnettech.com/de/produkte/c … 4port.html

For Win7 you require the FL1100 driver, Win10 has a built-in driver.

The driver uses a new interrupt model, which works more efficient (MSI, Message Signalled Interrupts).

Its best if RME answers / confirms your last two questions.

I am a bit curious on what would work best for pitch/varispeed purposes from external word clock.
On my UFX USB2.0 I tested pitch/varispeed from external word clock by one of the microsoft protocols(probably WDM) and it seems to work more stable in Cakewalk Sonar Platinium (last version before Bandlab). If I remember correctly I could pitch down as much as 2 or 3 semitones witout any issues by using word clock from an old Alesis BRC ADAT remote controller.

In ASIO Sonar switches samplerate to 88.2kHz when using external word clock to pitch down UFX a few percent( I can also see the RME USB driver do the same change of sample rate) . I assume the sample rate value is mandatory part of the information transmitted over ASIO.

Maybe there are no way to "fool" the ASIO sample rate and that what I am trying to do will never work over ASIO.

I would still like to upgrade to an UFX+ to get MADI support. 

So then I may need Thunderbolt later to get improved support for pitch/variaspeed. New DAW computer with thunderbolt is not cheap and I am happy with my current computer.   An HDSPe MADI (or HDSPe FX MADI) card may be cheaper than a new DAW computer with Thunderbolt support.

So that got me the idea that I may have the future option to interface UFX+ to my DAW computer via MADI and a HDSPe MADI card. Then I could also use far longer cables than Thunderbolt/USB3 and even move the computer to a different room.

Some new questions then.. :

1. Is it possible for the HDSPe MADI card to fully remote control both UFX+ and ADI-8 QS MADI via totalmix (over MADI coax pair) ?
(with UFX+ not connected to any computer via USB or Thunderbolt)

2. I assume HDSPe MADI card can simply use MADI from UFX+ as clock source ?
   (external word clock->UFX+>HDSPe MADI and my ADI-8 QS MADI to UFX+ over MADI)

3. Any additional limitations for external clock pitch/varispeed offset (mainly pitch down) in such a setup ?

Since the availability isn't that good atm, will this one (ASMedia, new chip) do it as well? I find the TB prices absurd imho. With regards to the ASMedia: I know it's not recommended in the manual, but since they are fairly new I wonder if they will work. Some other info. I am using 3 UAD3 Duo cards atm and a M.2 drive and am on Windows 10. So my guess is that with my X-99A (first gen) mobo I need to get rid of one of the UAD2 cards. So my plan is to sell em and buy an Octo instead.

Btw, The TB3 option card is like 90 euro's, then the cable and also the convertor will take another 120 or so from my bankaccount, which is ridiculous imho. So far my RME UFX+ isn't working since the beginning as it should. And yes It has its own port (Intel) and the other USB stuff, Mouse, Midi Keyboard(IKMultimedia) and Elicenser(Cubase) and Ilok, Midi Interface (Edirol UM880) are on the ASMedia controller.

But anyway, the sound quality is great, the drivers are still great, but USB-wise its a disaster so far for me. As soon as I begin to use all ports and pci lanes lots of errors show up in the driver program which isn't the fault of the UFX+ but really helpful to know how the system is performing. But nonetheless it crackles sometimes - sync error sounds.

I would love to upgrade to a better convertor sometime to add via MADI to the UFX+, but I am hesitating as you can imagine. First I really want to have a working solution. My HDSP9652 was showing better results back in the day - no crackles.

Other options:
So there is another option with the ASUS ThunderBolt EX3 PCIe card. I can use USB3.1 as well besides TB3 and DP1.2. That saves me the Startech adapter and TB cable.

But if I want to add another RME USB product like an ADI PRO2 (amazing product!) I am probably facing the same problems. So that made me thinking, lets buy another 2 or 4 port USB to PCIe card without the thunderbolt (EX3) option. And be more future proof.

But what's best? Do you guys over here have a recommendation?

My config:
UFX+ via USB3 (original cable that came in the box)
ARC USB
2 ALESIS Ai3's via ADAT.
MADI - na (fix problem first before investing... :-))
--
X99-A
16GB DDR4
5820K
ATI R7 250 silent from Saphire (http://www.sapphiretech.com/productdeti … p;lang=eng)
M2 970 Pro Evo 500GB
SSD 2TB Crucial MX300
SSD 830 PRo 256GB (obsolete, can live without it if that would help)
3 UAD2 DUO's
1 Edirol UM880
1 IK Multimedia IRIG Pro 37 USB / Or I switch to an Nektar P6 If I need the aftertouch. They don't have to be connected at the same time)
USB Mouse Logitech MX510 or 518, not sure :-)
PS2 Keyboard Acer
USB light which I sometime use
USB E-Licenser
USB iLok

Used buffers: 256 and 512.

If you guys need more info I am happy to share it.

Thank you very much ramses! I hope I can find that card somewhere, so far no luck. But on the other hand it look that I've solved the problem. I think it was the combination of the copy-protection dongles (2x) and the mouse that I've transferred to ASMEDIA usb hubs instead of the intel ones. The Asus X99-A has 5 USB 3 Superspeed Connections of which 4 are on the motherboard (so you can only use them via an adapter - grmbl) and one at the back (the one that isnt green and says: bios flash or something similar). And guess what, no sync errors anymore as it seems. I just can't believe it, but so far it works.

But again, If I can grab that card somewhere, that would be even better because of the 4.. LOL never mind, As I am typing this, the sync error is back again. (256 buffer and bitwig 2.4.3 with ASIO)

Hmm, thanks again, I would really like to grab such a card or maybe the EX3 from asus...

Ok, I couldn't cope with the fact that I had to buy new stuff so I took the liberty to dive in much further. Lots of great articles are here te be found. With two names popping up everytime. ramses and MC. Thanks guys! I've also checked a lot of other pages like Gearslutz and Windows tweaking sites etc.

I did a lot of things, but first of all:

• I removed two UAD2 duo's. Then

• I set my RAM at fixed speed (2400mhz if I recall it correctly)

• After that I used this command to fix my windows files: "sfc /scannow" in an administrator cmd prompt. Lots of files were fixed. Probably because I run this Windows 10 since Windows7 and was to lazy to do a clean install :-)

• Next: I've updated the drivers (not via Windows 10, but via AMD and Intel for the Vid Card and the 218NIC)

• I've disabled (again) the onboard soundcard

• Installed coreparking (tnx ramses!)

• instead of DPC latency checker which is bad for windows 10 and buggy according to a lot of people (also DAW builders)

• I've installed LatencyMon: https://www.resplendence.com/latencymon

• Shrinked my fixed page file on C (m.2) and put it on D (crucial MX300). Old size 6gb, now 2gb.

• Disabled all the background apps from Windows via Windows Settings > Privacy > Background Apps.

That's about it. Yesterday evening I didn't have any sync errors at all!. The buffersize is even lower (128 instead of 256) and I think I can push it even more!

So hopefully I don't need a Sonnet after all...

Thanks again Ramses!