note 8 speakerphone problem with messenger and google duo

[tosceb]

I use my note 8 for messenger video calls with my son 700km away. internet stable everything goes ok but after couple of second the speaker goes out in regular phone mode. I have to put the phone to my ear as a standard phone call. i stop the videocall and re-establish but after 10 secs to 1 minute, speakerphone goes out and there is no button to switch back to speakerphone. I tried Google Duo but same result so it is a phone problem not app problem. I tried clearing data, clearing cash, reboot, Nothing works. my wife has a S7 and has no problem like that. Please, somebody, HELP