Best way to play audio through car speakers w/out aux?

My 2005 BMW doesn't have any form of aux or bluetooth, and I'm wondering what the best way to play music from my phone through my car speakers for under $50 is. I currently have a cheap FM transmitter, but it has a ton of static, it's basically unusable. Not sure if it's because it's old and cheap, if i didn't tune it correctly, or if FM transmitters just don't work. Should I get a new transmitter, or is there a better alternative that doesn't cost too much?

you have a BMW and only $50 ? FM transmitters are junk, bluetooth is only slightly better. Might want to look around the BMW forum(s) and see if your model has an input for a CD changer that you you can approriate.