I checked the IPTV and found that the DM52xHD is not working as well as old boxes such as DM800HDpvr... (Yes !), DM800HDse, DM800HDseV2, DM500HD and DM500HDv2, like DM8000HD.
The DM7020HDv1 and v2 also have good images that support the new systems like IPTV.
The tests I done shown me that in fact it's not the "new" box that means it's better, but the software that is available for a box.
Personally I put back in it's box the DM520HD, and I prefer to use my old DM800HDseV1 that works much better also if the clock speed is half of it.
TS