I used to use an analog PCI TV capture card with older versions of MEP, and it worked fine. But now that TV in the states is all digital, I had to get new hardware.
The cheapest path for digital TV capture was a USB dongle. I think they're all the same hardware-wise. Mine in particular is an ATI Diamond USB digital/analog TV capture dongle. (Captures both over-the-air and cable signals.) It reports to Magix as an ATI AvStream. It comes with its own TV software but it also worked with Windows Media Center. (Which I've since uninstalled.)
Anyway, the dongle has never been recognized by Magix, either in MEP 2015 or 2016. Whereas, I just read the User Guide for Cyberlink's PowerDirector 14, and it says that they support capture of digital TV from USB. (In contrast to Magix, which appears to only support analog.)
I've tried Recording with my TV software enabled and disabled. Actually, I get close to working with the TV software enabled. When I do that, I can select channels from inside MEP and I can hear audio from the TV signal. But no picture and Magix reports no connection. As it stands now, I use the TV software that came with the dongle and record TV in MPEG, and then I import that to MEP. But it would be nice to do it all directly from inside MEP.
Is there a trick to this? Has anyone gotten a USB capture "card" to work with MEP? If so, how?