I've been using Garageband for a while now with my guitar. Using a 1/4" cable from my guitar to a 1/4" - 3.5 mm adapter into my input to my Macbook. This setup has recently quit working. I can, however, get my record player to input into Garageband. I first thought it was a bad cable or adapter, but both of those are still working (as well as my guitar). I've been working with audio cables for close to 6 years now, and this has really stumped me. Any help or suggestions are begged for!