this is happening on TF.

If I recall, this was a problem a number of people had with earlier iterations of TF. This is a memory problem, not mine, your computer's!

Try deleting your Call of Duty/uo/hunkusage.dat file, restart and see if that helps.

this happened to me ,set the hunksusage file in uo to 512, or half your computer memory,but nomore then 512...this done it for me.

Cross is right.
You have to choices.
Manually edit the uoconfig_mp.cfg located in your /uo directory
or
(press the tilde key "~" to open your console, then type /seta com_hunkmegs "256"

ty