I have also begun having these issues. I cleared the cache on my camera this weekend after being prompted to do so by the Samsung health checkup app to aid storage concerns. (I have no concerns- there is more than double the space left empty than I am currently using.) The next time I used the front facing camera it had these lines which resemble an mp3 sound line across the top fifth of the screen.
Did anyone get a resolution?
I tried clearing the cache again. I force stopped the camera app, tried other apps that also use the front camera, and even did a hard reset. None of these trouble shooting steps solved the issue.
If the issue is occurring in all apps, service would be recommended. I would be happy to see what options are available. Will you please send a private message with the full model code and IMEI number of the phone? http://bit.ly/2XERsky