Also make sure that the driver for the USB audio grabber was installed correctly and make sure that in the analog recording dialog that you have picked the correct driver in the audio driver selection that represents the USB video capture device and its audio inputs. If you can see two identically named entries for that driver in the list, switch between them and experiment with both drivers.
I am having the same problem. I redownloaded drivers, even downloaded a driver finder software. It still doesn't work.
It does capture audio/video fine in windows movie maker. I really wanna use MEP15+ though, due to the fact I can capture at a higher rate and make a better quality movie.
on my record screen it has 4 options, two have no audio, two have the weird rythmic scratching sound.
I finally got mine to work, double check all your connections and your drivers. I had to redownload/install my driver multiple times before it worked. but it does work now :)