We have been experiencing major issues recently with the connectivity of 2 Aironet 1310 bridges that are about 300 yard apart. They have been up and operational for nearly a year and within the last week they cannot negotiate a stable rate (1-54Mb). We have opened up numerous TAC cases in which we have validated the optimal settings. The only thing we have been able to reproduce is when we have the bridges associated and just connected direcly to our pc's on each end we can associate at stable rate of 54Mb. As soon as we plug them into our LAN switches it tanks and will bounce from 6Mb to 1 Mb. We have checked the speed duplex settings on the bridges and switches and left them at auto. I don't understand why if the rate has already been negotiated and stable that it is affected as soon as you put any significant amount of traffic accross it. The only piece of info I have noticed is the throttle counter will increment on the dot1q radio int. I have found no good information on to what the throttle counter indicates and if this having an effect on the rate. Any ideas would be greatly appreciated. Orginally the bridges were on 12.3 code and having issues, we were told to upgrade to 12.4 with no change.