I just switched my interfaces, moving from a Focusrite Forte to a shiny new Apollo Twin USB. Unfortunately, I'm having a problem with the Twin when used in conjunction with Sonar. 
 
Every 5-10 minutes, Sonar gives me the following message: "Audio Dropout: The audio engine has been stopped unexpectedly." This has happened during playback, during recording, and when I'm not doing anything at all.  (During recording/playback, the dropout is often accompanied by a high-pitched noise).  
 
I've looked at the "optimizing windows" pages for Sonar and Apollo USB, and have done pretty much everything they suggest. (Turned off sleep, turned off the ability of the computer to interrupt USB operation, etc.).  
 
Some additional info:
1. When I'm not using SONAR, everything is fine. (Monitoring through Apollo, using Apollo's console just for listening, playing guitar, etc.) 
2. The audio dropouts happen even when I'm not using any plugins in Sonar (only using the plugins in Console, ie, UADs DSP.)
3. The audio dropouts immediately "fix" themselves. After a second or two, normal operation resumes.  
4. I'm running a windows 10 computer. I7. 8gb of ram.  
5. I've tried changing latency/buffer settings, but I'm not entirely sure what I'm doing...
6. The dropouts happen even when I only have a single guitar track up.  
7. I never had a problem with audio dropouts when using my Focusrite Forte.  
 
Any advice would be very much appreciated. I really love this new interface, and It'd be great if I could get it working with Sonar!
 

Hi 
 
In the "Sync and Caching" section of Preferences I've done the following: 
 
I've set the "Playback I/O buffer size" to 512 and the "Record I/O buffer size" to 512 as well. Sonar had automatically set these to 256, and I was having trouble at that setting. I changed it to 512 because the Apollo's console app had the buffer size set at 512. I figured "matching" buffer sizes in my DAW with the Apollo console might help (but I have no idea what I'm doing!)  
 
***
 
In the "Driver Settings" section of preferences I am unable to change anything (the slider is greyed out). I am able to open the "Asio Panel" which just takes my to my Apollo's "settings" page. 

i have same Apollo unit and it is working great on my system. Similar specs but with 16gb ram.
make sure you are plugged into usb 3 ports. Also under device manager in the control panel go to the USB section and right click on USB Hub menu items, go to properties/power management and uncheck "allow the computer to turn off this device to save power". 
Sorry, that's about all I can offer.  Hopefully others can chime in.

belltunes
i have same Apollo unit and it is working great on my system. Similar specs but with 16gb ram.
make sure you are plugged into usb 3 ports. Also under device manager in the control panel go to the USB section and right click on USB Hub menu items, go to properties/power management and uncheck "allow the computer to turn off this device to save power". 
Sorry, that's about all I can offer.  Hopefully others can chime in.

Thanks, I appreciate it. I am going into my USB 3.0 port and I've already unchecked the "allow the computer to turn off this device" on all my USB hubs.  
 
These interface problems are so frustrating -- especially when you aren't computer savvy and have no idea what's wrong! I've pretty much come to the end of my rope, so I'm here :)
 

...one other thing. Best to use Intel usb 3 ports.

belltunes
...one other thing. Best to use Intel usb 3 ports.

Thanks, my laptop only has one usb3 port. Not sure if it's intel (and my understanding is you are supposed to use the ports that come with your pc, not an external one.)  

belltunes
...one other thing. Best to use Intel usb 3 ports.

I just had a thought: would you mind telling me your latency/buffer settings? Since we have close to the same system, I wonder if matching what you're doing would help.
 
Thanks!

Hi. You are using ASIO drivers, I hope. What kind of latency settings do you use? 
Below 10ms when tracking is for me good enough.
When I start to mix, I increase the latency, usually to the max.
All the best.
 

Zargg
Hi. You are using ASIO drivers, I hope. What kind of latency settings do you use? 
Below 10ms when tracking is for me good enough.
When I start to mix, I increase the latency, usually to the max.
All the best.
 

Yep, I'm using ASIO. I've just set the Apollo's "usb safety buffer" to "maximum" which is giving me a buffer of 1024. I've also set Sonar's "Playback I/O buffer size" and the "Record I/O buffer size" to 1024 as well.  
 
So far these settings are working -- no more dropouts! And since I can record (and monitor) in "real time" through Apollo's console, the huge latency I'm operating at doesn't really seem to matter. 
 
Still, I just don't understand why I need to use such a huge buffer. When I was running Amp sims (and monitoring them live) inside sonar with my Focusrite Forte, I was able to achieve much smaller latency. I figured the Apollo would be even better for latency because the onboard DSP would be giving SONAR (and thus my PC) a break. 
 
This hasn't been the case at all, and I have no idea why. So I'm still a bit worried that I'm doing something wrong...

My playback and record I/O are each set at 256.
Under 'Record Latency Adjustment (samples)'  Manual offset = 0, 'Use Asio reported latency' is checked, value = 1265
 
I can usually start recording at a setting of 64 samples. When there are quite a few tracks and the load is heavier I usually have to adjust to around 512 samples.  I usually mix with the sample rate on max.