When placing a video call, one side user is getting only five or six Frames Per Second (FPS), but the other side is getting the full 30 FPS, even with identical setups and configurations.
The speed at which a Cisco Video Telephony (VT) Advantage client is capable of encoding or decoding video is also highly dependant upon the speed of the CPU and the amount of available memory.
This can also be caused by low light conditions, CPU usage, or network problems. The issue is tracked in Cisco bug ID CSCee43075.
To resolve this issue, change the video card memory settings from 32MB to 64MB in the BIOS of the PC experiencing the slow frame rate.