I grab my windows phone 7.8 one day, and I find that no sound is coming out. At all. Neither speakers nor the headphones emit any type of sound. Songs, videos, alarms, nada. I had been playing songs on it only the previous day, and now nothing plays! If anyone has any answers, please let me know. I've already set it back to factory settings, but that didn't work. I need to fix this problem as sooooooon as possible.