[Xastir] Xastir under OSX: USB/serial connection to TNC?

[F1MHV]

Good day,

I installed NH6Z package (V2.0.1) for OSX on a MacBook Air running 10.7.5 and is running fine in APRS-IS mode. When I tried to connect an ArgentData OpenTracker USB in Kiss mode, setting /dev/tty.usbmodem"name" (name showing in apple's system profile) in TNC panel, Xastir frozen: any suggestion? I am not an expert of the Terminal...

Did anyone had some experiences/feedbacks using Xastir with SCS tracker thru the USB-serial connection?

73 de Cyril