MOTU Audio Express Problems

So I have a few problems with the MOTU Audio Express. Some might be because I am just new to using an audio interface, but I wonder how much is MOTU's problem.

• 1) The output volume is super loud (Way to loud for normal speakers) and can only seemed to be controlled by adjusting the volume knob for windows or the master bus level in Sonar, not the volume knob on the device itself or the settings in CueMix FX.
• 2) Every now and then I will play back an audio file and it will give nasty pops and crackles (which shouldn't happen as they play fine with internal audio). But if I change the sampling rate down to 44.1 it goes away.
• 3) When using it with sonar it works fine, until it just decides to blue screen my computer. The blue screens didn't start happening with sonar until I started using Audio Express. 

Thanks for the help in advance!

 
I have some MOTU gear but I don't know your particular unit.
 
1) You'll need to determine why/how to get the level knob on the MOTU to actually control your output. That has to be some simple oversight or aspect of how you are routing the output. Get that figured out so the knob actually does something for you.
 
There is a calibration procedure where you can take a pink noise sample that was prepared to play at -20dBFS and play it back while using an SPL meter to meter your speakers.
 
You set SONAR's "Main Outs" level slider to 0dB and adjust the knob on the MOTU until the pink noise is hovering at 83dBSPL.
 
If you don't have the SPL meter or the pink noise file (which you can find examples of for free on the internet) just play back a favorite song that has been CD ripped from SONAR and set your MOTU knob so that the volume is comfortable to you. That should do it for a couple years or until you move that knob again. 
 
2) Pops and Crackles might be drop out symptoms, which usually indicates you are pushing the system near it's threshold. If it works ok at 44.1 but not at higher settings then that is another clue that you are finding the threshold. You can try different sample buffer settings to see what gives you the most through put. You can tweak your computer to see if you can extend the threshold. You can try the different driver types. I like ASIO on my system... you may like the other choices.
 
3) Blue Screens happen when a driver gives up. The thing is, even if you do a crash dump and "prove" that the MOTU driver crashed you'll never know for sure what really caused the crashed driver to crash. In my experience MOTU drivers are really solid. If you have a recent driver you should probably look at other aspects of your setup.
 
 
Good luck.
 
best regards,
mike