byte 0xFF is sent double from Digi PortServer

I am using following Digi PortServer
Model: PortServer TS 4 MEI
Firmware Version: Version 82000747_X 02/07/2018

My current system requirement is to communicate with a serial device through ethernet connection, so we are using Digi PortServer as the serial to ethernet converter. It was observed that byte 0xFF (sent from serial device) will be sent double (0xFF 0xFF) in ethernet reception end, if “TCP Sockets” is selected as profile. It’s only sent once if “RealPort” is selected.

Since serial port is not accepted in my end, I am looking for alternative profile (or configuration, except “RealPort”) which allows me to receive data through Ethernet port. Duplicated 0xFF is causing issue to my system end. Thanks for advice!