Well I did changed my screen and it worked like a charm, at least was before I sold that stuff and bought new 5S. Replaced display was cool and not looking very promising.
Try: Start->Control Panel->Hardware and Sound->Device Manager. Uninstall the malfunctioned device driver. Reconnect. Also consider trying other USB ports.
That depends on what kind of blur is that. 1) If its motion blur, you are shooting in low light with low shutter speed and without a tripod. Your hands are not steady. 2) If its a lens blur: 2a: You are again shooting in low light and its difficult for auto-focus to distinguish between contrasts. 2b: There is something else going on with your lens focusing motor. (I ripped my auto-focus system out of my lens long ago, made my lens lightweight and more reliable). Note: Though I wouldn't recommend 2b's example. That would cost you your warranty.
Been there done that, in fact mine was loose so I "fevi-quicked" my headphone cable to the jack and when I pulled the headphone cable out, pretty much everything came out with it. So your options: 1) Change the chip-set.(too costly and not worth it) 2) Use USB sound-card, they usually give you far better sound. I am using steel series Siberia USB sound-card gives me 7.1 surround .
Just encountered the same problem on my iPhone 5 which is also out of warranty. The longer I leave it, the longer I get to work on it when its on again. Your post is from October 2014 so I was wondering you must have figured what's wrong by now. Care to share? Any help at this point of time would be appreciated.