I’m experiencing exactly the same problem. 3 days ago transparency mode
stopped working after being perfect (apart from the regular whistling)
for the past ~2 years. I have been using the APP2 as pseudo hearing
aids whilst watching TV or for casual meetings - I set up my audiogram
day 1 and it’s always worked fine. For some reason, possibly due to the
recent firmware update, it has abruptly stopped working. I even
bought a new paid of APP2 thinking my original ones were broken, but I
found those to behave exactly the same. I assume the original
functionality has been dropped to accommodate the new capabilities
advertised but those capabilities are not yet available in the UK. Very
annoyed is being mild.
I would take a stab at it and say you have updated to IOS 18.1 whether you realise it or not. If your iPhone has been set to auto update 18.1 will prevent you adding an Audiogram in Transparency Mode. Firmware 7B21 is not a problem as that is what I am using now with my iPhone on 17.7.1.
I set a new pair of AirPod Pro 2s up for my big sister today in the UK and she is really happy with them. She cannot believe that she can hear music properly again. She has mild to moderate hearing loss.
Annoyingly she had her update settings set to automatic on her iPhone and was on IOS 18.1 so I just set them up on her iPad mini that was on IOS 16.
If you have another Apple device that is running an older IOS you can set them up with no restrictions. An iPhone 12 is new enough. My wife's iPad 2018 works too.
The 18.1 update prevents you for using them in the way you have been in the UK.