Hi, since a few days a lot of 3cx users @ our company complain that they have problems with the sound. This problem doesn't appear always, but often, and i found out, that it happens only at users with vista machines. How to force this error (all the users use the latest version of 3cx client and 3cx server software is also the latest): I am calling intern user 20 (20 is a 3CX User with a Vista machine). I can't hear user 20, but he can hear me. Then i call him again, and it works fine. At the next call, i can't hear him again, and 1 call after i can hear him => every 2nd call i can hear him. Does anyone else have same problems? This problem didn't appear at all vista users...so i don't understand. Yesterday user with #15 had this problem, today it works fine at #15, but #20 has the same problem today?!?!?!