I initially thought it may be the tv I was using but I changed from Panasonic to Sony and the problem remains. So it definitely seems to be a sat box problem. Be interesting if there are different tuners used in the 5402 hd m3.
Also in my case the tv is ok, i've used a skystar with no problem on the AFN HD channel. I've open the 5402 but is not easy to understand what kind of tuner is mounted, on the side is present a sticker with the following numbers:
8CC20128ER
T81A08-VFF62
1406A25K01
No other informations is present on the tuner, and with this series on numbers i don't have found nothing