@georged thanks for the detailed reply. I agree that's probably not the issue as I can still definitely feel the presence of the button when clenching.
The more I think about it, I reckon having to close my mouth almost all the way shut to clench must be causing me to inadvertently lock my jaw up more.
The more I think about it, I reckon having to close my mouth almost all the way shut to clench must be causing me to inadvertently lock my jaw up more.