Feedback From my Monitors

[SincereEnt]

I just installed the Protools Mbox onto my PC. Everytime I start Windows Media Player, Reason, Or Protools, I get that annoying NEeeEEeee sound from my monitors. ANy Suggestions? I checked up my set up like one million times so I dont think the set up of the Hardware is causing the problem.

 

[Middleman]

Do you use a headset with mic off your soundcard? Sometimes this can trigger feedback.

 

[SincereEnt]

headset

I dont have a set