One forum not sending out email notifications

I belong to a number of forums and almost always have e-mail notifications sent out for that thread I was in getting new activity.
This one isn't;
https://www.avsforum.com/forums/

I have contacted two different "administrators' and they are claiming it's my browser (naturally). I cleared cash & cookies as instructed and unchecked, then re-checked e-mail notifications in the threads list I'm following, but no difference.

The stranger thing, the 'Conversations' (PM's) notifications do come in. I even change my e-mail address, but no difference. And yes, I've check my Spam folder. I have no firewalls.
I have run into this elsewhere on occasion, but not to this level.

Any ideas here??

Not sure why it would be your browser when it would surely be a profile setting?
I've not posted on there since 2010. Amazed all my old posts are still there!

Having logged in I can only see these settings in Accounts > Preferences:
I assume you've set them all correctly.

Email options:

• Receive email when a new conversation message is received

Content options:

• Automatically watch content you create…
• and receive email notifications
• Automatically watch content you interact with…
• and receive email notifications