All your posts are visible so don't worry.
As for your faxing inconsistency, seems like you are doing all the right things. 1 other thing you can try is to put your Fax machine behind a DSL filter; folks have reported positive results in the past.
Some back ground:
by Bobby B » Mon Aug 15, 2011 4:17 pm
“A few weeks ago all Telos received fax tone detection support, which allows the Telo to change to an uncompressed codec when a fax call is detected. As a result of this change, the manual fax mode parameter is no longer needed. We're in the process of updating the documentation to reflect this change”.
Try testing with the HP Fax test number:
I tried the HP Fax Test number 1-888-473-2963 fully expecting it to not to work.
But it worked fine. Within five minutes I received a return Fax from the HP Fax Test number.
I have read where some people after connecting their Fax machine directly to the Ooma device Phone port, with nothing else connected, allows the Fax to work. (But mine goes all the way across the house with other phones connected, without any problems).
Others have said that after making adjustments to the Quality of Service settings in Ooma Setup, (and their router, if the Ooma device is connected after the router), their Fax began to work properly.
Also try dialing the complete number including the 1, example 1-xxx-xxx-xxxx. (Also try dialing the number 1-xxx-xxx-xxxx-# adding the hash mark to speed dialing). Remember that with Ooma, any call in the USA isn't long distance. For some Fax machines you have to add a pause or two after dialing the 1.
If you have ten digit dialing enabled in My Ooma, https://my.ooma.com/system, you can dial without using the 1 for long distance numbers.
A DSL filter, installed in the reverse direction, in the phone line going from the Ooma device to the Fax phone port, has helped some people.