Instruct: Classify Amazon reviews into positive or negative sentiment
Query: I'll be returning it

I had a lot of optimism for this because my girlfriend has aGriffin FM transmitter for her ipod and it works great. I liked the awesome display and that it could operate on batteries. The only problem is that it doesn't work. I tried it in both of my cars (a truck and a car) and I held it all over the interior of both cars trying to find the "sweet spot" but I couldn't. I also tried going up the whole FM frequency and couldn't find anything that would work. In frustration I picked up the Sony cassette adapter and it works perfectly and sounds great. Oh well.