Hi, Upgraded from an S3 to an S4 active this week. Love the phone, but having big issues with the signal strength. At my desk I previously had full strength signal and H+ which allowed me to stream video via Sky Go/iPlayer in high quality with no problem. I can only seem to pick up 'E' on the S4a, despite having 5 bars of signal. It also struggles to pick up decent data signal at home. Any ideas?