Resolve Wi-Fi and Bluetooth issues caused by wireless interference
Recommended settings for Wi-Fi routers and access points
1 - Restart in Safe Mode. This will perform a Disk Repair, clear cache files and only load Apple Software, extensions and fonts. The boot up will be slow and can take some time - Normal.
2 - Does the issue present in this mode ?
3 - Sometimes a Safe Boot followed by a Normal Boot will just put things right.
4 - If not - there could be something in the main User Account playing up. To further isolate this - Set up users, guests, and groups on Mac. Then log out of the Main User account and log into the dummy account and test again if the issue persists.
5 - If the issue is present in the dummy account - then, this appears to be a System Wide issue on the computer.
Understand, we are all working Remotely from all around the world.
Therefore, we do not have the On-Hands experience the User ( you ) has with this computer.
The next best thing for us to having a semi - actual On-Hand experience on this computer is to follow the steps below
Download the Application Etrecheck directly from a well Respected ASC Contributor. And Safe to use.
The application is free or paid from added features.
Run the application with Full Disc Access ( Security & Privacy - Full Disc Access ).
It will take a Snap Shot - both the hardware and software.
The Report will Not Reveal Any Personal Information.
Post back the Full Report - copy and paste - using the Additional Text Icon ( 3rd Icon to last )
We can have a look at the report for possible issues and may have possible suggestions to resolve the issues.