HELP! Microphone Auto Muted!?

To start off, as useful info, I am running Win XP. I am a gamer who uses Ventrilo as a guild chat system, and recently I had a new sound card installed. After my dad and I went through heck installing it and figuring out the drivers and getting my sound to function correctly, we found out something odd. Whenever I try to get on Vent, I always have to double-click to open my Play Controls, and un-check all the mute boxes that seem to automatically be checked to mute, especially my mic. Then, I have to go Start> Settings> Control Panel> Sounds and Audio Devices> Audio Tab> Sound Recording Volume Button and open the Recording Control box and Select check my Mic to get it to work, so I can chat in Vent. However, even if I keep these two volume control boxes open, they periodically auto-check the mute boxes and un-check the select box.
Does anyone out there know how to get this to stop??? Much thanks in advance for your help!