Loss of sound

Here's a tough one for anyone who is up to the challenge. I recently encountered two problems that may be related:

1. I'm not getting any sound (through either earphones or speakers) when I try to play a Presonus file I've converted to a WAV file or an MP3 file.

2. I'm not getting any sound through my headphones when I try to add a track to an existing Presonus file, and the overdubbed track doesn't record. Here's the path I've been taking to overdub an existing file:

Add track, open Song, go to Song Setup, then to Audio I/O. Under inputs, Add Mono, Add Input, Apply. Under Outputs, click Q Mix, Apply, OK, then hit Z on the console.

The strange thing is that both of these functions were working just fine until a few days ago. Two other points to consider:

-- I get sound through both headphones and speakers when I play back a song I've just recorded on the Presonus system.

-- I recently upgraded to Studio One v2.6.2, and installed it on my D Drive (as opposed to my C Drive) in Windows 7 to conserve available space, but that seemed to work fine -- for awhile.

I would greatly appreciate any advise anyone can give me about this situation. I'm stumped.

This message was edited 1 time. Last update was at 01/06/2014 16:38:05

Studio One folder is like 170 mb bro, it's important to install main program on C HD.

try asio4all or reinstall S1