Car bluetooth not working

This app is great but whenever I connect it to my car bluetooth its not working and keeps playing sounds from my phone
If would fix it please it will be nice....
And one more thing, why I cannot play the musics in background even when I close my phone it will stop, I have to keep my phone on all the time and I cannot use any other apps
Thanks

Waed1110 about SoundHound - Music Discovery, v7.1.5