Lenndon

Hello

I bought a beomic bm5 and built a cable for it.
But something strange is going on...

The bm6 part (the lower mic) is working just fine

but the bm7 (upper part) is extremely quiete.
There is something coming in my motu, but its about twice as quiete as the bm6 part. It is pretty much impossible to record with it.

My question is:
What could that be?

I looked up the cable.. nothing wrong

Is it needed to exchange the ribbon?
And if so, why do I still get sound from it and it is not completely broke?

Thanks for any advice