I bought 2 Arduinos NG, one works fine but the other one has a small glitch. As soon as I plug it in, the TX led goes on and won't turn off. It still can upload programs and sends data (just tried with a piezo, MaxMSP seems to read it flawlessly).
It's not such a vital problem, although I don't get the blinking feedback I normally would.
Any suggestions?
I suggest you contact your dealer to ask a warranty exchange, if possible.
If not, you can try finding the origin of the problem, measuring the led voltages, and the wires continuity with a multimeter.