Hi, Ukerm,
thanks for your information. I don't think this problem can easily be solved. At least not with 2.5 GHz processors. The same thing is true for the alternative freenetTV, which has recently provided a beta-version of their software for the Mac. You can read the test by Mac & i here:
https://www.heise.de/mac-and-i/artikel/DVB-T2-HD-auf-dem-Mac-Erster-Test-des-Freenet-Sticks-3672604.html
They used a Mac mini with 2.6 GHz, the CPU load was at 340% (!!!), the Mac got hot and the ventilator was noisy, just the same when I tried to use my eyeTV stick. You can hear the processor acting up and the ventilator getting noisy. The freenetTV also reacted very sensibly to problems with antenna reception. Same as with eyeTV. My dealer took the stick back, great thanks to him, and as I rarely watch TV and only non commercial stations, I'm contenting myself with using live streams.