I have an iPhone5s on 8.1.3. For about the last two months while I'm at my desk in my home office my calls drop in the middle of a conversation. I need to walk away from my desk in order to resume the call and to get it to stay connected. I've not installed any new devices in my office. I have tried rebooting and resetting my phone, but it still happens. I'm not sure how to resolve this but it is affecting my business because the disruption frustrates my customers. I switched from Sprint to Verizon for this very reason 3 years ago and haven't had an issue until now.