Issue with Spider Port 11 UART Com1 9600 Baud

Hi, had a Problem with the FEZ Spider.

I have connected a RFID Antenna to the Port described above.

I guess every 5´th read was correct. All other were bad reads. After ~5 mins the connection was dead.
After power down/up the connection starts again.

After connecting the RFID to another Port (Port 4, Com2) The Antenna has only good reads, and the connection was good for hours.
Did you know about a Problem with Port11?
I don´t care about this Problem anymore, but perhaps i can save this Time for another User reading this post.

The RFID was a Conrad Towitek antenna using standart TTL Levels at 9600 Baud, it was connected to a breakout bord +5V/GND/Pin4
Did i miss something?

All serial ports share the exact same code and work identical. I am not sure.

Thats pretty much the same setup i have my spider working with an ID12 RFID chip. I cant rember which port i had it connected to though. I will have to check when i get home.
I didnt get any problems like yours.

Ok, it was all my fault grml regarding a german webside about Gadgeteer i took pin 4 for RX(a little error). 5 was the right one.

pretty funny that i have received any Data at all.