Source:  AIOCOMX

Explanation:  AIOCOMX detected an 8250/16450 UART device in the port and set the maximum port speed to 2,400bps.

Action:  If 2,400 bps is an acceptable maximum port speed, no action is required. If you know that the port hardware will support a higher speed, you can use the MAXRATE= command line parameter with the LOAD AIOCOMX command to set a higher maximum port speed.

You can view the command line load parameters by entering the LOAD AIOCOMX ?command.