Well dodgy net connections could be this issue.
Overloaded lines etc.
Even though I have fibre, these days especially the net is really used.
Sometimes my echo responces take 20 seconds to come accross.
Data can take some time to get from place to place.
I have had a few things like that.
I am still getting the data at the right speed but its all from outside.
I suspect because of covid among other things the international
networks are just getting used.
So much of the net depends on cloud infrastructure well.
If thats not the case either of you could be using wrong channels for wireless.
You can get an idea of what everyone uses with something like
wifiinfoview from nersoft.
You will have to change your channels on your router yourself, they
are all different.
Then there is the placement of wireless hardware.
I have laptops and so do others I remote for.
Laptops are fine, but if you have a desktop and use a standard
internal card, depending where the unit is or even where the card is
you can get poor quality.
On a desktop I used the unit was close but under a desk under the user
the wireless card was at the bottem of the case and that was enough to
really play havoc with audio.
The user changed to a usb dongle placed on top of the same unit and
there was no issue after that.
If you do not use fibre, the same thing could apply with cable.
If you still use copper then they are not as strong as fibre, I used
to get noisy lines and broken connections needing someone to fix more
often than I would care for.
When I got the latest one 2 years back the isp simply switched me to
fibre and I got a better plan and that be it.
If you happen to use mobile wireless broadband signals and congestion
can vary widely.