I’ve had that…and for example when I get it while running Cantabile, stopping and starting the Cantabile audio engine usually seems to fix it. But it also happens when not running Cantabile. I’ve never managed to get to the bottom of it, but fortunately the workaround on my Cantabile box tends to work…
Neil
Yes same here, it suddenly happens, louds cracks in series. And indeed resetting the audio engine solves it.
It’s ok with Cantabile. But I can’t do this in reaper because I have a whole show running there.
Is that the only workaround?
What is the audiocard function function in Cantabile? Can it be send by midi?
I think @brad will have the best insight into this - what exactly Cantabile is doing when you toggle the audio engine, that could stop the Ultralite crackling. Perhaps when you re-enable the audio engine, it reconfigures the driver in some way, which is correcting something (total guesswork here!).
Neil
This would be intresting to know, So I could have an EMERGENCY button on stage 
It’s better to have the show stopped for 1 sec. by pressing a button then I have to stop it all and reset the audio driver.
If I have more people confirming this, I will address this to Motu. Their support isn’t great but when it’s this important maybe they would look at it?
I asked them before for help, because my USB port suddenly half recognised the motu. I was on stage and BAM it didn’t work anymore.
I later found out that pulling out the USB while the Motu was connected caused the problem and using the other USB port solved the problem.
Only way to resolve it was to system restore Windows before that point. Until you accidently pull out the usb cable again 
Strangely enough Cantabile has no problems with it, only in Reaper?
I contacted Motu but they only directed me to a local support. Yeah right…
I even bought a Roland Octacapture. But it wouldn’t install because I downgraded my Windows to much for music reliability LOL So I’m sending it back. Motu has better functionality anyway. Only pitty about those 2 problems. Risky business on stage.
I went through quite an ordeal with both my MOTU Ultralite mk3 hybrid and the 828 mk3 hybrid boxes.
This is a link to what eventually solved it for me. If you have ever uninstalled and reinstalled the drivers, or plugged into a different USB slot so it re-loaded the drivers, this will possibly help you also.
You actually needn’t remove all of the drivers and reinstall from scratch - only removing the “ghost” drivers usually is enough.
Terry
BTW - MOTU’s phone support really tries hard to help, and I seldom have been kept waiting on hold.
617.576.3066 - tech support (9am-6pm EST M-F)
Terry
Thx Terry, i’m in Belgium, so that’s not easy I guess.
What? Aren’t long distance rates to Boston, USA from Belgium only, like, $10 a minute or something? 
Well, be prepared to wait for a MOTU tech link support request, but once they latch onto it, they usually don’t let go until you are fixed. Still, try this approach detailed in that post. Worked for me!
The other issue that has happened to me was when I tried to use the S/PDIF with another box - even with the master/slave sync settings set up, it still seemed to lose sync at times. That has been less of a problem recently for some reason. Lots of little “Windows” things can throw off the sync - like YouTube videos switching between 44100 and 48000 sample rates, which really make things go crazy sometimes.
Terry
I now suddenly had it when I started Cantabile up.
So nothing strange happened here 
Allright !!!
I’m loving this software !!!
Maybe the Power button flips to ‘null engine’ and then back to the last used driver?
Ok, my motu was working till now on that particular port, suddenly it doesn’t.Propably I hot switched an other than the motu, usb port I guess :-/
Frustrating.
I don’t have any insights into what might be causing this, but to answer the question about what happens when Cantabile’s audio engine is restarted:
Startup is basically the opposite of the above.
Also, in case you need it, Cantabile has a restart engine binding that you could bind a panic button to if needed.
Your software is great !
Did you get a chance to try what I mentioned above in this post?
Terry
Ow i missed that, let me see for it today.
So these are the steps?
Pitty the Motu helpdesk didn’t guide me to this info, seems like a common problem :-/
The proper way to reinstall drivers:
- Turn off the MOTU device and unconnected it from the PC
- Uninstall the MOTU Hardware program from windows control panel Programs and Features (formerly Add/Remove Programs)
- Open the Device Manager, drop-down the View menu and select, “Show Hidden Devices” and right-click and delete all instances of the MOTU driver elements found there, in both the “Audio Inputs and Outputs” section AND the MOTU ones under “Sound, Video and Game Controllers”.
- Restart the PC
- Install the driver software (currently MOTU Universal Audio Installer 4.0.5.9644)
- Restart the PC (again)
- When windows is fully loaded, reconnect the MOTU device, turn it on, and let the drivers install. This takes about a full minute to complete - watch the Device Manager Audio Inputs and Outputs field and you can see them popping back in. Your Windows Audio (from the speaker icon) should show all the devices listed there also now.
- Done
Nope, that didn’t work :-/
Followed all the steps, uninstalled, removed the drivers from the system in 2 places, restart, install latest drivers, restart,…
Same problem: only my left usb port works (left one abandoned me yesterday)
Strange thing: it suddenly did work with Cantabile. But propably because I removed the usb port from an other device it changed. Or was it the cracks yesterday that almost scared my whole household here?
Anyway, it works on the left USB port, but my fear is it will fail on me in a live situation.
Risky business…
And still I’m loving the Motu card…
I find it particularly odd that your PC only sees the MOTU box on one of the ports.
In the Device Manager, with “Show Hidden” checked, hunt around in the second View option, “Devices by Connection” and see if any of your USB’s are disabled. (Unused ones will be grayed out, but that is normal.)
I would not normally recommend trying to uninstall USB ports to make them behave, but then again, it might work.
Each time you move the MOTU to a different USB port, check “Show Hidden” and look in the “Audio inputs and outputs” section (viewing “Devices by Type” again) to see if you have “ghost” MOTU drivers. Just uninstall the ghosts - you should not need to reinstall the MOTU drivers again. It seems to get confused as to which USB port it is in if the “ghosts” are there and starts going crazy.
Of course, doing the factory reset maneuver on the Ultralite is a good thing to do before re-starting the computer, just in case it is carrying over some of its internal freaking out to the PC settings.
Terry
Thx, I’ll try this later