Unfortunately, it turned out to be completely useless as the driver programs on the CD, website, and Windows Update are not compatible with Windows kernel isolation, and it is ridiculous to require disabling a security feature for the product to work.
Even so, I disabled kernel isolation and followed the instructions, which show in the diagram at the top to connect it first and then install the programs, while below they say the opposite (if they can't even create a proper instruction manual, what can one expect from the driver programs).
After a lot of confusion and MANY restarts, I managed to get the program installed by Windows through Windows Update to work (no mention of the other two) but the fact that I had to leave kernel isolation disabled made me decide not to use it on my main computer after all.
Otherwise, it worked fine on a netbook with Garuda, but what can I do with that.
Meanwhile, the included ArcSoft program is a disaster as it constantly crashes and the menus are user-unfriendly. However, there are alternatives (some even mentioned in another review), so it's not a big deal.
Maybe it's Microsoft's fault, maybe it's TerraTec's fault, maybe it's the fool who bought this product. What a shame...

Well guys, for 25 euros it's decent, for the 10 euros I got it for, it's really perfect.

The only thing that might concern you is the mcx connector, which requires an adapter and therefore makes it fragile. Also, since it is very small, it requires caution, especially with a heavy coaxial cable, as it can break from both sides. It goes without saying that all these cards require a good signal from a central antenna or alternatively, an internally amplified one near a window.

With a good free third-party program like dvbviewer or smartdvb, it performs well, but it may pixelate a bit after a few hours (especially on AMD APUs), where a restart of the application or reconnecting fixes it. With the provided program totalmedia, don't even bother. I recommend smartdvb, lightweight with all the features like timeshift, pause, record, etc.

***It works perfectly on all Windows versions, including Windows 10 and 11, but make sure to download the correct drivers for Windows 10, as there are none available for Windows 11 and do not use Windows Update. FROM HERE --->>> https://www.terratec.de/details.php?artnr=145259&lang=en

*IMPORTANT* If you do a direct installation, uninstall it from the device manager and then install the drivers. You must accept the installation of the audio hardware and restart. In the device manager, it should say >>>MONO mini stick HD, if it mentions something else, it won't work, so change the port and if it still doesn't recognize it correctly, reinstall it. It may not work properly on a non-powered hub where you have other devices, I think it prefers USB 2 and directly connected to the PC. Also, because I have both Intel and AMD APUs 3200g/3400g, the card seems to work better on Intel with a dedicated GPU.

***Also, for AMD users with third-party programs, disable hardware acceleration/decoder wherever you see it in the settings of the respective application or the LAV decoder.

In the photo, you can see it compared to other cards and I played a movie on it because I have already replaced at least 2 adapters that easily break. Overall, if you are still looking for cards to buy, only go for Avermedia.