Sorry to hear about the recent issues you have been experiencing.
Do you have the AudioBox driver called Universal Control installed: http://www.presonus.com/support/downloads/audiobox-usb
Test basic audio function by turning the Mixer knob all the way to the right, then testing audio playback from iTunes, or Youtube.
Because this may be a bit more involved than the Answers system is set up for, I recommend that you create a support ticket if you require further assistance on this issue.
Here is a link to create a ticket: http://support.presonus.com/hc/en-us/requests/new