Volume on Aux-In is Very Low

[4jacks]

Hello, I have a 2003 Z4 3.0i with BMW Business Radio.

I recently installed this Aux-In Cable:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I also installed a Ground Loop Noise Isolator:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

My problem is that when I switch to AUX and play music from my phone I need to crank up the volume on the Radio to max, (Despite the Phone already being at normal volume.) When I switch back to radio or CD I need to quickly lower the volume. I made a quick video showing the problem:

https://vid.me/5is9
(Volume Warning on some parts of the video)

Is there any setting to adjust this, or other solution?

Thanks

[Onizukachan]

You can try pressing radio preset 1-6. On my e46 is level of aux.
on our e83 which is like your z radio, it does squat.
Th phone should be at max when playing back on headphone jack, and the rest is what it is. Unless you have a poor connection somewhere.

[4jacks]

Thank you I will try that.

Yeah the problem is that whether I turn the phone to max or the radio to max, I always forget to turn it down. I actually think it's less deadly when it's my car radio versus me putting my headphones on and pressing play with max volume on my phone.