Roll20 lower the micro everytime i speak

Hi everyone, One of my player has this problem: Everytime she speaks, roll20 lower his mic until no sound can be heard. We use TS3 and she can see the volume button in TS3 being lowered when she starts to talk, she is the only one that have this problem. She doesn't have the "Let other application take control of TS3" box checked and it only happened on Roll20. When she quits teh page, everything return to normal. Any solutions ? 

Has she checked her windows settings? If not have her go to  Control Panel -> Hardware and Sound -> Sound -> Audio properties -> Communications tab Select Do Nothing from the dropdown box. Apply & OK. If this does not solve her problem, please have her post in this thread so we can start the troubleshooting procedures.

She didn't had "do nothing" checked! I will see if that solve the problem at the next session, but thanks a lot if that's the solution ^^