From
@trankilou above regarding Bluetooth, also make sure your antenna is connected.
Bluetooth range is a bit short. I need to keep my speaker literally within 50cm from the antenna
See my post about this issue. Try to be connected to a 5GHz WiFi and the range of your BT should increase. You can check level (dam) using "alt" when clicking on BT in the top menu
You will need to adjust your symbols to an iMac 18,3 from 19,1 I believe to have your CPU information show correctly. You can use Clover Configurator to make the change, log out of iCloud first.