not playing from SD Card since connecting phone

I hope I can explain this clearly as possible, here goes...

Using an Amundsen SatNav/Media Player in my Fabia Monte Carlo Tech, up until this morning I was playing songs from a SD Card with no problems whatsoever. However, this morning I paired up (bluetooth) my new Smartphone - successfully as far as I'm aware, but since doing this I'm finding that when I press the Media tab on the unit from any other function (ie SatNav, Radio, Phone) the player then goes straight to playing from my phone!

It was a little confusing at first as I have same music files on the phone as I do on my SD Card. I then switched off my phone's Bluetooth but the player then refused point blank to play from my SD Card! I've since checked the SD Card which plays fine through other media (laptop).

How could pairing up my Smartphone have caused this? There wasn't a problem when I previously had my (un)smartphone paired.

Thanks in advance for any help or assistance,

Glyn