Need help with plugins!

Hello, I have a big problem with all sounds generating plug ins. 



I usually make an audio track, load my plug in into the audio track and then i make a midi track
connect the midi track to the plug in so i can build sounds in piano roll. 

Whenever i do this i start building my sounds and editing them which all works like a charm. 
Then i plug my guitar (for example) into my Presonus Audiobox USB and record some tunes with that.

But after about 30 minutes for no reason the audio track which produces the sounds from the plug in just stops making any sounds at all. 
I still see the volume bar on the midi track indicating when it hits a note but it doesn´t play. 

Here is a screenshot trying to explain the problem:

have you tried the audio and midi reset buttons (the 2 icons at the bottom left of the transport window in the transport section of the control bar).

What audio drivers are you using?  ASIO I hope!!!!

Are you sure Track 3 has output still set to Track 2's synth?

The problem went away for a short while when i restarted my computer. 
But i'd rather solve it then reboot every 30 minutes. 

You could try raising your MIDI buffers (not your sound card buffers) higher that what there set at now.
Go to Preferences > Playback and Recording and raise your "Prepare Using  ____ Millisecond Buffers under playback to 500, 600 or even 800.

Checking your power options so there always on, like others have said, is a good idea also

CJ