Bass loss with volume and alerts level

Hey guys! I tried figuring out on my own but can’t find the answer. Is anyone else experiencing loss of bass after few seconds? I’ll try to explain. I have the prime xse premium with JBL premium sound. At first when I raise volume from let’s say 10 to 35-40 I feel the base for about 4-5 seconds and very happy with it. It sounds pretty good and deep enough. But then 5 seconds later the bass seem to wash down and adjust and lowers. As if someone slowly turns the bass down. I think it’s some sort of speaker self preservation/protection setting. I am sensitive to it and it almost makes me little dizzy when it does that. (I know weird. Some inner ear BS perhaps) I have self level for speed adjustment off. I am likely adding subwoofer. But even with that it will still adjust likely. Anyone else has the same experience?

my other question is in regards to blinds spot monitoring and parking sensors volume. It is little too low than what I am used to. Any way to raise the volume / alert sound for both blinds spot alert and parking sensors?

Thank you!