General discussion of using Roboclaw motor controllers
The problem starts, if using command "74 - Set S3, S4 and S5 Modes". The command is acknowledged, but after some movement the module starts to send data without request. In my case it is sending the version-string instead of the ACK for an encoder-request.
As I said in my last post, I will need to see your code to determine the problem. If you can, post a simplified version that just has enough code to show the problem. Anything that requires special hardware will prevent me from being able to run the code so try to remove anything like that from your example.