Just wanted to put it out there, if you have an aftermarket radio (Pioneer, Alpine, etc...) that has a data port (Pioneer has IP-Bus, Alpine has AI-Net, I don't know of other brands), you can get an adapter for data port to rca, then adapter from rca to 3.5mm, then you can use your car speakers!
Now if your radio already has bluetooth or a 3.5mm jack, then you're good to go, but just so you know since the TP2 has a 3.5mm jack.