kharrang wrote:Sorry to be dense here, but I can't tell in all this discussion if there's a solution to my problem
OK, you seem to have a two-part problem:
1) Radio plays instead of podcasts when you start the car. Can't help you there.
2) Radio plays too loudly when you start the car. There may be some hope for this one:
My understanding is that the infotainment system remembers the audio volume separately for each input. The trick is that you have to adjust the volume while that input is playing. If you adjust the volume while playing USB, it doesn't affect the volume of the radio, etc. So I think what you need to try is to turn down the volume of the radio while the radio is playing, and turn up the volume of your podcast while the podcast is playing.