I would just try repeating them after a good recording many times in a row, multiple times a day, until you can pronounce them well without the recording. Some people may take a little longer to memorize the right pronunciation, but I can imagine that they are also the ones who will never forget it afterwards.
As a Chinese learner, I think you can download the audios or videos so that you can repeat the pronunciation. You know that practice makes perfect.
What's more, if you wanna have a better pronunciation and master Chinese better, maybe you need talk more with a native speaker. Try finding a friend to have one-on-one chats in Chinese with or an actual tutor to practice with, which makes Chinese a part of your daily life.
Hope it can help you.
My experience is that for 2 years I didn't really pay attention to tones when I did the SRS repetitions.
Honestly, it didn't matter too much in the every day life, most people understood me anyway and I wanted to focus full speed on expanding vocabulary.
But then I decided that I had to do better than that, so I started to include the tones in my answers for the SRS repetitions.
What I mean is that before, I would put "perfectly remember / remember / barely remember" even if I had the wrong tone but that I knew what the character meant.
Now, I will put "forgotten" if my tone is wrong for single characters (if the flashcard is only 1 chinese character), and if it is multiple characters and I have 1 tone wrong inside, I usually still mark "correct" but then I immediately divide my score by 4.
The immediate effect is that you end up with much more daily flashcards as you have a lot more wrong answers.
But it really worked. After about 1 month I could remember almost all the tones of the characters I already knew.