USB 5220 can't tune to any DVB-T channel (no signal)

[bobi]

I've just received a brand new TBS 5220.
Unfortunately, I can't tune to any DVB-T channel.
Scan failed by constantly showing signal strength level of 50% and quality 20%, on EVERY frequency.

I've an external TV box DVB-T tuner tuned to my local TV provider frequency (514MHz), but the TBS USB can't find any signal at that frequency.

I've tested on both Windows XP SP3 desktop, and Windows Vista SP1 laptop, with TBS Viewer, DBS Dream, and VLC player, with driver version 1.0.0.5.
In all cases I got the same results.

I'm afraid I received a faulty device. Any idea what can I do?