loudspeaker during call goes off autonatically

[iamviveksri]

i switch on the loudspeaker during a call by touching the speaker icon on the Phone app. after some time i find that altough the icon is still on, the loud sound has gone. then i touch the icon again to first switch it off and then again to switch it on and the loud sound is restored. it is very irritating to see that what is otherwise 'flagship' phone of the company has such issues

[Lykia]

I don't have any of those issues.
You can try out this:
Settings》Apps》three dots upper right corner 》show system apps 》Phone》Storage》Clear Data

If it doesn't work then you can boot into SAFE MODE and try it again.
If it does work then uninstall one by one your apps till it works again.

If that doesn't work either then you can bring your phone to a Samsung service centre for a diagnostic test.