hi! I updated my s7 (g930f) and showed same symptoms plus the ff:
1. wifi is connected but unable to connect to internet. Im sure that my wifi is working just fine as all my devices are connected at the moment, no issues whatsoever. tried forgetting networks and restarting my wifi, didnt work.
2. youtube videos unable to play after a while
3. notifications (and other media including games) has no sound, but samsung music plays
Anyway, here are the solutions I tried and what finally worked
all worked TEMPORARILY
1. restart device
2. cleared system and app cache
3. tinkering with the advance options
4. easy mute feature: off
5. and finally, factory reset (i know, sucks)
I was at my wit's end after the factory reset because if a reset wont cure it, it means I would have to wait for another update, which we know takes forever.
Anyway, I was determined to solve it. After the reset i made sure no rogue or illegal apps are installed. Ive deleted all games or other apps I otherwise dont need. I used only my barebones app plus youtube, pinterest, messenger and facebook.
I figured if the issues still come up, then it must be within these apps.
And finally found one solution that so far WORKS:
I deleted the facebook app and now using facebook on the internet browser. I know, it is odd.
But hear me out. I observed that when I get these errors I have the ff apps opened: youtube, Pinterest, messenger and facebook.
youtube, messenger and pinterest seem to be ok, Im using them now and im error free.
I deleted the facebook app and did a restart and my wifi seems even faster.
Ive been plagued by these issues for weeks and just happy to finally find the solution (or so i think), and it's not as drastic as a factory reset. You might want to give it a try, if not I suggest you do the reset and start installing apps you need and observe which ones trigger the issues.
Will update if it recurs