Muffled USB microphone for MacPro

I have been using the same headset brand for 2 years, for a yoga studio.  Two weeks ago the quality of the sound is muffled. We know it’s not the mic as it works with a non Mac laptop.  It works but its terrible quality.  We reverted back to the last OS version, Monterrey… better but still muffled.  We are using the Electro-Voice R300-E-C Wireless Headset.  any help would be great….