Compatibility with the M1306B?



I have a .NET 2.0 C# program communicating with the M1306B and it’s working fine. If I switch to Supreme 10,
things stop working. With a serial port sniffer I can see that my program works normal and stuff gets sent,
but no response is ever given from the Supreme 10. If I “hotplug” the M1306B just by switching the serial
cable, data starts to flow again. I tried with two Supremes, both straight from the package, and both of
them not answering.

The funny thing is that with Putty, the Supremes work fine. I can call with the AT commands and so on.
But using the SerialPort class, I cannot get an answer. I think I already tried every settings combination

Is there some configuration option that I’ve missed?