Issues using iPhone with USB port

[pvrismore]

Hi there, new to this forum and new to DS3's in general. I recently purchased a 64 plate model.
It has the USB/aux and bluetooth but it doesn't have the touchscreen, however it has a better
quality display than the very base model DS3's (hope that makes sense as I don't know what else to call the display).
Anyway.. The issue that I'm having is very odd and I can't make any sense of it so was hoping that someone on here had a better knowledge

I plugged my iPhone into the USB port of the car and it always defaults to my iTunes music (I primarily use Spotify), which is fine as my old car did too.
However my issue is that I will switch it to Spotify but if I use the skip buttons on the control stalk, it will switch back to iTunes. Not only does it switch to iTunes,
it plays this selection of about 10 songs every time. I do not know how it generates this selection but it is the same songs every time it happens. It also happens if I do
listen through iTunes. For example, if I choose an album to play and then hit skip, it will go back to this collection of songs instead of skipping to the next track in the album.

I have an aftermarket radio that I took with me out of my old car that i could fit. but that really is a last resort for me as I'd rather have the clean look and complete functionality that comes from the stock unit.

Any advice would be great, I'm tempted to go to my local Citroen dealer to see if they know anything but I don't want them charging me a fortune.

Cheers

EDIT: I apologise if this has been discussed before but I searched around the forum for around 15 mins and couldn't find anything on it.

[BenS]

Pretty sure the USB will default to the internally stored music on the device i.e. your iTunes music. It probably plays the same 10 songs because they're in the first playlist in the list it opens, and switches whenever you use the controls because it's treating the iPhone as an MP3 player and not an extension of the phone controls.

Try making a folder called "driving tunes" and put whatever you want to listen to in there, then navigate to that folder before you start driving. If you want to listen to Spotify either keep using it as you are without the stalk controls or use an aux jack lead - either way you lose the controls as it's streamed music not stored music.

OR... connect it via Bluetooth instead of USB and Spotify should work with the controls then.