Volume keys as in F10 + , F11 - or Mute F12 ?
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 - 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 the Developer.
The application is free or paid from added features.
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.