MOTU Audio Express issues

I run one on Win 8 64 bit with no issues, I am outputting via SPDIF tho.
 
Have you tried updating the firmware?

The driver listed as the current one for that interface is: v4.0.5.7483 May 1, 2013
 
The current firmware version for that interface is: 1.04 January 2, 2013
 
In addition, in the manual, it appears from the text that you may be able to control volume to different sets of outputs, by pushing in the volume knob and holding until the desired output's led lights.  Perhaps this can be used to produce sound from Mains rather than just the 5/6 pair.
 
Here is the relevant text from the manual (link to manual: http://cdn-data.motu.com/manuals/firewire-usb-audio/Audio_Express_User_Guide_Win.pdf)  - If this applies and my understanding is correct, this may explain why it is currently only producing on output pair 5/6.  (so, follow the below to get output to mains):
 
Main outs
In a standard studio configuration, the main outs
are intended for a pair of studio monitors, but they
can also be used as regular outputs for any
purpose. Their reference level is +4dB. Use the
front panel VOL knob to adjust the Main out
volume. Push the VOL knob until you see +main
LED turn red (or flash red) and then turn it to
adjust the main output volume.
 
I hope that helps.  Please note that the above manual, though the current one, appears to be from a slightly older version of the interface drivers, though I wouldn't think that would affect this piece of functionality. 
 
Bob Bone
 
 

Thanks for the post back.
 
I understand you have your drivers installed on your laptop.  It working on XP is not relevant to your Windows 7 issues.  My listing of the drivers and firmware were more for the other individual, since his are out of date.
 
What is not clear is whether or not you have properly set the Volume Knob to point to the Mains - so that adjusting the volume knob will actually raise the volume level of the mains, which is why I included the documentation snippet.  If so, great, but I did not see that reflected in your post.
 
I did not see any complaints out on the web about this particular issue, so it is not likely an issue with the drivers, for whatever the worth.
 
Bob Bone
 

I understand - at least there is output, even if it looks a little lost on its way to the mains.  :)
 
Bob Bone

Also have you got any onboard sound devices? If so, disable those.
 
Also, you said you only have one USB 2.0 port. Windows can be a bit of a nightmare if over time you have connected many devices to that port.
 
So, in device manager, under "view" click on the "show hidden devices" and then manually clear out any devices that you dont use. (Do this while the MOTU is unplugged)
 
Then Plug back in the MOTU and let Windows freshly install it to your port.