Hi David,
Welcome to the forum; sorry for your trouble.
First guesses:
In your Windows Sound settings, did you set FxSound as the Default Device?
Have you tried also setting the FxSound device as the Default Communications Device yet (see tip by Vijay below)?
Did you disable Exclusive Mode and the option to decrease volume on incoming calls?
And some more configuration recommendations:
In Windows Sound Settings, make sure all your devices match at the setting “24 bit 48000 Hz” (max);
In Windows Sound Settings, disable all Enhancements, including Loudness Equalization, for all devices (except for FxSound which doesn’t have this tab);
In Windows Sound Settings, disable Hardware Acceleration;
Again in Windows Sound Settings, disable all devices you don’t use, including the hidden ones.
Please let me know your status after checking off the above points.
If the problem persists, we will explore further options.