John,
I would love nothing more than to be saying you have helped me solve this issue and it is an issue. I went over there and changed the answer mode to triple and all other rings and it simply would not answer anything but double, so after messing around with it, I ended up putting it back on the exact settings I started with, but I used my cell to call the voice number three different times and it did not answer (it should not have) and confirmed it did answer the double ring (ring master) number and it did.
However, it seems the first voice call after I left the darn fax machine answered the voice call. :-( - This really is an issue as the fax is worthless now as they have to keep it off so they can get voice calls.
While I was there (remember I am doing this remote or as much as I can) I did see and played with the answer mode for "fax / tel" and that had some promise to offer relief, but while I was there I did not leave the machine on that mode. After I learned it was not working still I had my dad go through the menu settings and change the answer mode to this (fax / tel) and we are now testing it on this mode. This is not ideal or even acceptable, but perhaps lets them answer voice calls without the annoying fax tone. Receiving faxes has not been tested but I would imagine that will work and I should test that by sending one their way.
Something is clearly wrong with double ring answer mode settings where it picks up normal single rings. I keep hoping to see a firmware update with something about faxing as one of the fixes but I have not at the time of posting the original post. I did however, install the latest firmware just in case before making that first post, but the issue is still present and very annoying. Dad will keep it turned off if it does not work as it should and that means HP has FAILED miserably on this. It should do as expected and it's not.
I did have high hopes that one of the other answer mode settings would work after reading your reply as I'd also agree if it's not working as expected its probably a config error, but I am sorry to report I don't think that is the case here.
As much as I don't want to go down this road, it appears a call to HP is required and that just means for lack of wanting to go through the BS when calling, the call will not get done before it's out of warranty.
I really do thank you for chiming in here!
Rob