Same.
I have stopped recommending Razer products after that update combined the audio devices and broke THX on my headsets. Was really hoping for a rollback! Still debating on selling my Razer stuff on FB and going another route.
Only workaround for the broken THX I have come up with is to set the headset within the Razer Synapse app to Stereo with a custom flat EQ, uncheck Exclusive Mode boxes (Advanced tab) for the device within Windows Audio Devices, and use the Dolby ATMOS app (I already own) with your previous Razer EQ settings applied to Custom 1.
This also fixes things like audio bugs in apps like CrewChief (for racing sims).
Not too sure if the paid THX app provides a similar workaround since I have yet to buy it considering my headset is suppose to include it.
Edit: Trying the THX app trial since it has been mentioned across many threads. $20 is steep though!
Edit: Mirrored my original THX EQ settings on the THX app and it sounded like poo. Reverted back to the Razer headset THX after and it was a little better but gunshots are muffled. Dolby ATMOS sounds great compared to the two THX methods.