Hey Alnatio,
Just to confirm i have the same thing. It seems to be a Fanvil issue rather than a 3cx one, though 3cx does appear to make it harder to switch to a different ring-tone. As far as our main office is concerned the new tone is identical to the one used for internal calls (it's not, but...
Hey @Charles_3CX
Hope it's okay responding to this thread as i don't believe the query differs in the slightest (and this is the top response every which way i google it).
We've recently deployed a v20 solution to a Middle School i work at (still using v18 at the Secondary School) and this is...