I am on my third replacement because of reception/connectivity issues, the signal appears to be strong but placing your hand around the back of the phone at the bottom causes the signal to degrade significantly also network data is very touch and go. I can be in the middle of town with a perfect HSPA signal and get very mediocre results sometimes it just doesn't work at all. I have tried three replacement SIMs, changing the GSM voice codecs, flashing different baseband radio firmwares all with no positive results. I also tried my partners SIM which is on a different network and had the same problem. I'm just starting to think that the antenna design is not very good and has low-gain characteristics, although that wouldn't explain why the connection is still unstable despite the baseband reporting a strong signal.
Another problems is absolutely terrible call quality, there is lots of white noise in the background, speech is distorted sometimes, pops, clicks, and just general instability. I've read so many different threads on many forums with people describing the same issues, and they too went through many replacement handsets and different SIM cards.
Please someone tell me there is a fix for this or it is at least a known issue otherwise I'm going to return this POS and get the Galaxy S4 instead. My previous phone SGS3 was great with reception! Bah! I'll cast it to Davey Jone's locker... release the kraken!!