I’ve just recieved my 3.5mm to 2.5mm audio adapter from Proporta, which came really quickly, they’ve gave me a free promotional code which they said I can share so here it is: PASSITON10. Just need to get a line-in cable or tape adapter and my car has digital audio!

Update: I forgot to mention - they also sent me a free Earl Grey teabag. Quite a strange thing to send out, but I enjoyed it.