Hi Mate,
Connect to your phone.
Copy the file to your desktop sys.txt
Open it
find the file line
navigation_audio_stream=4

- If you do not have it, enter it in the section
[android]

if you have it - a change to a different number starting with 1
After the change, save the file.
Copy the changed file to your phone.
Go into the folder SAVE - check the contents and remove!
Quit
Start iGO and check if it works Dynamic Volume (you can see it only in the real rides)
.........................
PS.
For starters, remove all skin skin's folder and check if it works