On my way in to work yesterday morning, I listened to music from my iPhone4 that is paired via bluetooth to an upgraded SMH10 headset (upgraded to 4.0). On the freeway (60-70mph), I had no trouble hearing the music. When I got to work, I shut the headset off (the music was still playing, I think).
When I left in the evening, on the same freeway, at the same speed, the music was really quiet, so I tried turning it up. I got an "it's at the max volume" beep, and tried to convince myself that it was just noisier from the wind. When I got off the freeway, I shut off the SMH10, then turned it back on, and then started playing music again, and it was LOUD.
There seems to be some sort of issue with the volume level, have others noticed this?