I am no native speaker. I have been reading an English book lot since 1970. Last 3.5 years I have been listening to A.J.Hoge and CNN. I have understood A.J. Hoge from the beginning and today I understand him 100%. Contrary, I understand CNN speakers only 20% or nothing. My Ears are normal from 10Hz to 250Hz, it needs only 10 dB. After 250 Hz to 8000 Hz, my ears need more and more dB to 100 dB. My ears are the same for both, A.J.Hoge and CNN. It is a big difference between 20% or nothing and 100%. I think A.J.Hoge speak at a higher volume every part of words and sentences, but CNN speakers not. They pronounce parts of words with low dB for my ears. I have discovered what I hear that I understand, what I do not hear I do not understand. Higher volume on my TV or Computer can't solve my problem because there are higher noises also. What do you think is the problem here? Maybe CNN speakers would need to be students of A.J.Hoge because their interest is to be clear to all, native and no native speakers.
Do the announcers speak at the same rate? Do they use the same accent? In the 1990s, a study found that Boston news announcers spoke twice as fast as Los Angeles news announcers. Atlanta is in a third dialect region of the United States.– JasperMar 26, 2019 at 23:01
Adding to Jasper's comment, could it also be that we can more easily pick up the vocal patterns of one person versus a diverse group of people such as you would have on CNN?– Don B.Mar 26, 2019 at 23:36
CNN is relatively easy, because its pronunciations are clear and meanings are explict. Some TV series are really diffcult.– ZhangMar 27, 2019 at 4:01
I just Googled A.J. Hoge and the answer is simple. He is an English teacher and be speaks very slowly, with pauses, and with very precise enunciation. He does this to make it easier for his students to follow him.
Unfortunately, CNN make no such effort. The newsreaders and many guests will speak fast, with unclear enunciation, and with a large number of idioms and technical phrases.
The only solution is to keep working at it. Good luck.
Or try the BBC world service and see if that's any easier. Sometimes radio has better sound and is easier to concentrate on than television.