ImageRunner C2550 distinctive ring or disable incoming fax

Hello!

I have a Canon Color ImageRunner C2550.

Are there settings somewhere for configuring distinctive ring?

Failing that, is there a setting for disabling incoming fax?  I found this post: https://www.copytechnet.com/forums/canon/141171-canon-ir-c2550-turn-off-fax-receive-post795020.html?141171=#post795020 Similar to this poster, it appears the seventh bit is already 1. Or...do you count from the other way when doing this?

Any help offered would be most appreciated!

- Joshua