I use WhatsApp but not so much for video calls but I haven't noticed a volume/ speaker issue.
I use x5 ring products which include two ring doorbells, and both the speaker definitely work @mrrrob
Do run the phone's Diagnostic Tool in the Samsung Members App to see if that highlights anything.
If not a broad sword troubleshooting step option is this > Clear Cache Files from the phone's System Partition Section > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop or use a Tv's USB Port to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too { Possibly excluding the s²⁴ Series of phone's }
Daily Driver > Samsung Galaxy s²⁵ Ultra 512Gb ~ Titanium Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
