Recently after upgrading IP Office to release 10.1 we got calls from different customers who told us that they have about two seconds of silence at the beginning of a call. After researching with one of our customers we figured out that only 9608G phones are affected while other models (9611G, 9641GS) has no problems. In our tests showed that only outbound calls are affected and only calls with direct media (no VCM calls and no RTP relay calls) are affected.

The phone were running different firmware versions and we did an upgrade to 6.6401 as it is the latest firmware that ships with IP Office 10.1. But that didn’t help. Due to the fact that 9611 phones that run the same firmware have no issues we thought of a bad series of hardware. Continue reading →