Headset volume too low during VoIP calls

[Guest Jan K]

When I tested VoIP (via sip.voipbuster.com) and used the headphones, the volume was too low - I barely could hear what the other party was saying. The volume on the Vox was set to maximum as well as the volume slider on the headphones. (No problems with the headphones while making regular calls.)

Has anybody experienced the same? Does anybody know how to fix it?

Best,

Jan