I recently switched from an iPhone to a Lumia 928. As soon as I did I started having problems. Some of them have been outlined here, like it being stuck in headphone mode. Also, when I shut mine off it turns back on immediately, and the signal goes from great 4G to no service while sitting in the exact same spot. But, I didn't get my phone from Verizon, I bought it from a friend. Is there any fixes to these problems, and would Verizon replace my phone?