Are you on Mac or Windows?
If on Mac then I can't help much, but as for Windows:
Check your sound devices to see which are enabled and which are set as default. Also make sure that you don't have any other sound cards/AIs plugged in.
I used to have that problem and that's how I solved mine.
Go into Control Panel> Sound and Hardware>Device Manager. expand Sound Video and Game Controllers, right click "IDT High Definiton Audio CODEC" (or similar) then "disable".
Shut down then reboot and the PC should either find the AI or tell you how to install audio hard ware. You might have to re install the AI drivers.
If this works then go and find the audio section to shut off "Windows Sounds" those irritating bleeps and bloops that can screw your music!
This assumes Windows 7, if you have XP it is similar and even easier. If W8 you are on your own bub!
Dave.
W8 is a nightmare. Hard to navigate and hard to find anything. We all eventually learn but the curve is great with this release. I hated Vista more though
W8 is a nightmare. Hard to navigate and hard to find anything. We all eventually learn but the curve is great with this release. I hated Vista more though