I am having a setup as follows:
Berbee Singlewire 2.1
Cisco WLC 5508 running 6.0
Cisco 7925 Phones
The Wireless network for voice is configured with 802.11a (as we are going to use bluetooth also) and for multicasting (enabled multicast address on WLCs is 18.104.22.168 same as PTT application).
The PTT is working fine on the wired network phones (7911) with good audio but on the wireless we are facing bad quality voice being garbled, robotic and very choppy.
If anybody has got a similar setup working, would be glad to know how they fine-tuned to resolve this issue.