You can turn the stereo on (to proceed with the story), then turn it off immediately and still get the achievement, but only if you turn it back on just before the end part of the game.
I used a save game near the end part, just before Hoaguie and Laverne travels back in time, and it worked for me.
Bernard has to turn the stereo on BEFORE making the 3 of this steps:
- Activated the time machine for Laverne
- make a call to buy a diamond and activate it
- Activated the time machine for Hoagie ( my last step)
As Voodo melon more clearly says (thanks), you can do 2 of 3 steps, and then turn on the Stereo.
Based on NeverwinterLune solution at truetrophies:
Thanks to The Reverend JC, yes, you have to turn it on before the end part, it's anioning to hear the noise all the time.