My mobile microphone not working properly when i use voice recorder , video recording .Sometimes it work .But in the timing of calling , it works properly .Whats the possible cause of it ?

I used galaxy a50s model.In this device , when i used camera ,Mobile has heated up .I check that there are no app run in background.But I facethis problem every time when i use my mobile's camera .Please tell me the solution 

A50s me jo software update ka problem houya tha oo solve kiya keya Samsung ne ?

There are lots of extra problems have came to my mobile when I update my galaxy a50s mobile to one ui 2.5Major problems are,1.more battery drain2.camera over heated3. Phone will heated when it is charged in fast charging.