Those are not no ordinary hearing Aids, they are MFi hearing Aids that appear to offer bi-directional bluetooth connection:
ReSound
- ReSound Cala
- ReSound ENZO
- ReSound ENZO2
- ReSound ENZO 3D
- ReSound ENZO Q
- ReSound Forte
- Resound Key
- ReSound Lancio
- ReSound LiNX
- ReSound LiNX Quattro
- ReSound LiNX TS
- ReSound LiNX2
- ReSound LiNX 3D
- ReSound Nexia*
- ReSound Omnia*
- ReSound One*
- ReSound Preza
- ReSound Prima
- ReSound Sola
- ReSound SOUSA Fine
- ReSound Up Smart
- ReSound Vibrant
- ReSound Vida
- ReSound Wing*
MFi hearing devices marked with an asterisk (*) in the list above use bidirectional streaming, which allows you to talk hands-free. MFi hearing devices without an asterisk use unidirectional streaming.
I have reasoned Linx Quattro, NOT bi-directional, so mine are using the iPhone microphone, using the method described above, you should hab=ve the resound 3D App active on your iPhone to make adjustments.
Use Made for iPhone hearing devices - Apple Support
I suggest you contact your hearing Provider, to get explicit guidance and coaching on exactly how to use the bi-directional feature.