If your Phonak is still under warranty, ask your audi to return them for replacement because you deem them defective for not being able to provide you with a consistent hearing experience since your audi kept on insisting that she didn’t change anything in the programming. After all, the HAs may actually be defective for real, not necessarily in a failure non-operable way, but has marginal failure that cause inconsistency in your hearing experience.
Make sure you insist on replacement and not repair due to the nature of the issues.
Maybe a new pair will still have the same issue, but at least you will have eliminated that variable that it’s not the actual HAs themselves and not the programming that are misbehaving.
I remember reading a post on this forum about a Phonak user who had a great experience trialing a pair of Phonak HAs, but when she starts wearing the pair that she purchased, it didn’t perform as well as the demo pair. She eventually was able to return the pair she purchased, went to a different audi and purchased the same brand and model from this new audi, and this second purchased pair works out fine for her. The point of this story is that it’s possible that maybe there’s a quality issue with Phonak HAs that cause inconsistent hearing experiences and maybe a different pair of the same brand and model may work out better for you. It’s worth giving that a try. At least that is within your right to exercise the option if it’s still under warranty.
The thread I was talking about above is in this link http://www.hearingaidforums.com/showthread.php?21388-Dilemma-re-Phonak-B-R-90s