Complementing my previous appeal, in this I want to tell you how I managed to temporarily fix synapse and apply the settings inside it.
1. Completely remove Synapse and install version 3 from the website.
2. Connect your headphones to the synapse, then configure all the settings as you need.
3. Close the synapse, remove it from the system startup, then reboot the system.
4. Open synapse as administrator, check your settings, Next, hold down the mode switch button on the right earcup for 7-8 seconds until a sound alert (First beep, then speech)
5. Connect your headphones via Bluetooth to your phone without disconnecting them from your PC. Then go to any application and check the operation of the equalizer, to do this, press the mode switch button once, you should immediately notice the difference.
6. After that, in your phone's Bluetooth settings, manually disconnect the headphones (or turn off Bluetooth)
The synapse setting will then be applied to the headphones. I'm not sure, but if you want to change some parameter in the synapse, you will have to do all these steps again.
enjoy and share the results