If I was having this problem, here is what I would do:
-I would uninstall the helix software on your PC
-reboot
-install an older version of the HXEdit software 3.11 maybe
-the new features of 3.5 on your Helix won't work, don't worry we wont be using them.
-reboot
-it might be helpful to track down the helix drivers installed and copy and paste them into a backup folder
-install the latest version of HXEdit manually or use the update thing in the right hand corner of the program
-reboot
-give it a test
-if you have no desktop audio, do the rollback thing. Windows should have archived the previous driver. If it did not, then browse for the drivers I said to copy/paste into a backup folder.
I hope this helps.