This is just a recommendation for those who, for any reason, might want to play a MP3 player, CD player, USB flash drive, or other audio output device through their car radio.
I tried out eight different FM modulators of the type that transmits an FM signal through the air to be received by your car radio. I was very disappointed with the results. Not a one of them was in any way usable at all. The signal went up and down, the background noise was unacceptable. They were all a disaster, and some cost up to $80 (luckily I bought them all with a return privlege).
Then I came across an FM modulator that plugs into your cigarette lighter and into which you attach a MP3 player (CD player or other audio output unit) via an audio cable (supplied). Or, as an option, you can also insert a USB flash drive directly into a USB port on the modulator. This product is called the "VR3 MP3 FM Modulator", made by Virtual Reality Sound Labs, and can be seen at
I have been very satisfied with both voice and music played through this device via the audio cable. Music played from USB flash drives however seems to lack adequate bass. This device does stick out somewhat from the dash so you must make sure it will not interfere with your dash controls.
I bought this modulator at Costco for $26, including sales tax.