Yes they were enabled. I've tried different combinations of enabling/disabling but have had no success. Does the message waiting indicator work for anyone else using an OBi ATA device?
Works for me using the same settings described above on my OBi202.
If your VoIP provider has multiple accounts and VM boxes try checking to see that the account you're logging into is bound to the VM box you're checking. Otherwise your provider may not be sending the MWI signal to the account. If you still have problems post your VoIP provider and others who have experience with the provider might chime in with more specific suggestions.