generally all of the FM transmitters have a staticky sound to them. i had them for an older car at one point in time but returned it the same week. it also was not the cheapest model available. i ended up putting a new head unit in to fix the bad sound.
to verify, your car completely lacks a 3.5mm or other aux input jack? (new cars often have it inside the armrest) that would be the most ideal way. same with bluetooth, if its available.
if you must use a fm transmitter then you could give something like this a go http
/thewirecutter.com/reviews/best-fm-transmitter/ as this one gets the best reviews for the price. keep in mind that what channel you tune to also is important. you want it to be different then local stations so you do not get interference.