For some time, we have been aware that a very occasional race condition can result in a deadlock in TURNS TCP sockets, which then results in TURNS connections failing. While rare, once the problem occurs the only resolution is to reboot the affected Media Server.
Testing shows that this issue reproduces only at very high load, and has been occurring since at least LiveSwitch 1.8.0. If you have not noticed the issue in your LiveSwitch installation then it is very likely that your traffic is not high enough to trigger the problem.
This issue was resolved in LiveSwitch 1.11.0.