Hi,
Well, you need an interface to record into your computer...Analog mixers do not have this capability. First, before you condemn your 44 please allow me to introduce you to the VSL knowledge base:
http://support.presonus.com/forums/20568836-AudioBox-VSL-Series
There you will find a wealth of knowledge, and things to try. If you haven't done so, please go to your My Presonus account and register your products. Once you have done so, open the 44 in the "hardware" tab and there you should find the drivers for your product. It is very important to keep up with the latest drivers for a problem free experience.
Should this not be the case, and you are up to date driver, and software wise, then start a Tech service ticket and they will get you sorted!
Best regards