I have a PC based mt router with 3 sparklan (wl-760a) ar5213 card configured to 2.4GHz b/g mode and some ar5213 based card for 5GHz.
5GHz working fine, but on the 2.4GHz card I can’t select manual data rate, because most of clients can’t connect when I select manual data rate with any kind of any data rate. When I leave on default data rate all clients can connect. I try a lot of version from 2.9.7 to 2.9.50 but the problem is exists 
I was angry because nobody answered for me and I try cracked 2.9.27. It’s looks like working, but only looks like… 
I bought other licence (MT 3.0) with another cf card, but the problem is exists… 
I made the new 3.0 totally new configuration, not backup restore!!!
On other place with the same hardware configuration the problem not exists!!! I don’t believe that all of sparklan cards was broken on the same time!
May I send supout.rif?