iPhone SE problems on 11.0: apps freezing and voice call problems Right after update to 11.0.0 (and all further updates up to 11.0.3) my iPhone SE experience became quite painful. I have two different symptoms:  


Many apps are freezing for several seconds at random moments often. 
In few days after iPhone restart I can't hear my callers (and vice versa), when I restart my phone the problem is fixed for next few
days.


It's a 1 year old 64 GB iPhone SE MLM72RU/A which worked perfectly 1 month ago.
You should backup your iPhone SE with iCloud backup.
Then restore it to factory by using iTunes on a computer (Mac or PC/Windows). This will erase the entire phone (hence why a backup is recommended 1st) then it will install iOS 11 with a fresh install. Not with layers of patches, which is what you currently have). After the restore is done, and the iPhone says hello, then you can set up the iPhone and then restore from iCloud backup. That should help with the software problems. 

As for the calling aspect, if it pops up again, remove and re-insert your SIM card tray into the iPhone (right hand side of the phone). If the issue persists afterwards, reset all settings.