Adjusting my own Signia 7AX hearing aids

I have come to the end of the line with my audiologist because it’s costing me an arm and a leg and it’s never right. I have Signia 7AX hearing aids.

Basically I feel like the amplified (through the microphones) sound keeps changing. Recently my right ear went down in volume and also high frequencies. I thought I was losing more of my hearing which was depressing but then I realised that streaming directly to my ears sounds absolutely great (and hasn’t changed).

Last time I went to see the audiologist he did a new hearing test and set the hearing aids up again (because he’d lost my previous settings) and it was worse than it was before. I also get the impression he doesn’t know what he’s doing with the software.

So I’m looking at getting a NOAH Link thing and using the Connexx software (which I already have). Is this viable? I know it will void the warranty but I’m so frustrated with his inability to make anything right.

One thing I want to do is reduce the vocal frequencies in my left ear which I believe is causing slight distortion and is very annoying.

Thanks!