I have an MOTU 896mk3 Hybrid which has both USB 2.0 and Firewire connectivity.  I had two new MOTU 896mk3 Hybrid's.  The first one was sent back and later a second one was purchased (and I still have it).  The MOTU replaced a Roland Octa-Capture that had no problems with the USB 3.0 port so I reused the USB cable from the Octa-Capture with the MOTU.  I would get intermittent dropouts.  With the second one I finally realized I had USB 2.0 ports on the front panel and tried one of those and NO dropouts. 
 
When I built my new PC, back in early December, it only has USB 3.0 ports so I ordered a PCIe Firewire 400/800 card with a T.I. Chipset.  I'm using that and no problems (and same low latency).
 
There is a thread on the Gearslutz forum about "MOTU Windows 10 Stability" which turned out to be others complaining about the USB 3.0 dropouts with MOTU USB units.  Something to be aware of if you buy a MOTU unit with only USB 2.0 connectivity.  In somewhat defense of MOTU they only mention USB 2.0 on the page for the 896mk3 Hybrid, although USB 3.0 port is supposed to be backward compatible with USB 2.0.  I have many old USB 2.0 devices and they work without problems on USB 3.0. Even my old Frontier Tranzport that was built in the Vista days before USB 3.0 was even thought of works OK with USB 3.0 port and Win 10 (although I had to install the Tranzport Vista driver in a compatibility mode when I installed it in Win 10).
 
Here is the link to the gearslutz thread:
 https://www.gearslutz.com...dows-10-stability.html

I've got my sights set on this one.  It totally has exactly what I need and then extra via the digital. 
The fact that it is also a stand alone mixer with remote control is the icing on the cake. I was looking seriously at all the new digital mixers and this is the same price point and it's a Motu, I would imagine none of those other brand, Behringer or Soundcraft have as good a driver as a Motu.  Very rare to find any negative reviews of Motu interfaces.  
My computers all have both USB 2.0 and 3.0 so I'm OK for now. But I was planing on a new laptop to use with this live and I don't think USB 2.0 is an option anymore.  
https://www.sweetwater.com/store/detail/UltraLite4

I'm wrestling with this as well.  For me, its between this one and the Tascam 20x20.  My studio rig has USB 2.0 (its got a few years on it) but my laptop only has USB 3.0.  This would be a no brainer for me if it weren't for the reported driver issues.  I may still end up with it, though.

Ya but now there are reports of issues with Tascam drivers too. It will be fixed no doubt as both company's seem on the ball about drivers. Tascam in tha past sucked but they certainly have improved since Gibson took over and they are apparently writing their own now. And I would think the Motu issue will be quickly resolved. It seems it only certain interfaces anyhow same as the Tascam issue. Probably all related to W10 updates screwing things up.
 
 
 
 
 

Its not just Win 10.  I had a dual boot with Win 7/Win 10 when I got the MOTU and I had the same problem on both.
 
From posts on the referenced Gearslutz thread it doesn't look too promising for new MOTU drivers and responses some have got from MOTU.  I opened a problem with MOTU when I had the first unit and MOTU responded timely and was friendly but I got the impression nothing was going to happen even when I reported that it worked OK on USB 2.0 but not with USB 3.0 ports.
 
As I mentioned on another thread, based on responses I got from MOTU, I won't be buying any more MOTU.

FWIW, Even if your motherboard only has USB3 ports in the backplane area, most have two USB-2 headers where you can connect a USB2 bracket (less than $10).  
 
Most issues with USB-2 audio interfaces result from connecting them to third-party (non-Intel) USB-3 controllers.
Very similar to connecting a Firewire audio interface to a non-TI Chipset Firewire controller.

Jim, a general question re USB 2/3...my laptop has both. Except for my external disk drive, I just use whichever port is physically convenient. I don't use a USB audio interface, so we're talking slow devices such as mice and MIDI controllers. If speed is not an issue, is there any reason to make a point of matching USB3 devices to USB3 ports and USB2 to USB2? Power limitations, perhaps?

Jim Roseberry
FWIW, Even if your motherboard only has USB3 ports in the backplane area, most have two USB-2 headers where you can connect a USB2 bracket (less than $10).  
 
Most issues with USB-2 audio interfaces result from connecting them to third-party (non-Intel) USB-3 controllers.
Very similar to connecting a Firewire audio interface to a non-TI Chipset Firewire controller.

Good info to know.  My desktop rig has both USB2 and USB 3 (but I think I have to choose between SATA 3 and USB 3 - its an old MB) so I don't think I have an issue there.
 
Jim, my laptop is the concern as it only has USB 3 ports.  Do Sager/Clevo machines use Intel USB 3 controllers (and if this is some of your special sauce that you would prefer not to share - I understand)?

This has to be my problem as my new laptop only has USB 3, which, contrary to popular advertisement, is NOT 100% backward compatible.
 

The beauty of USB 3.0 is its backward compatibility with USB 2.0; you need a new cable and new host adapter (or, one of the Asus or Gigabyte motherboards that supports USB 3.0) to achieve USB 3.0, but you can still use the device on a USB 2.0 port and achieve typical USB 2.0 performance.
www.pcworld.com/article/186566/USB_3_Finally_Arrives.html

 
My MOTU unit is only a few years old but will not work with USB 3.
 
My Behringer works sometimes/sometimes not with USB 3. It also does weird things like slowely light up the transport buttons one by one until they're all lit when using Kontakt player standalone.

Soens, are you on Win 10?  If not, it definitely won't work.  USB 3 on Win 7 is problematic for almost every interface.