I'm totally happy with mine and haven't experienced any problems with hizzzing, hdmi issues or lip sync. I do have a belkin surge protector and have it connected to a satellite hd receiver, PS3, HTPC. The only concern is when selecting picture mode- custom, horizontal lines flicker on and off so I don't use it. I just leave it on through or direct mode. I haven't downloaded any firmware yet either, are there any benefits doing so?
Media room- LG 4K OLED EG9600, Pioneer Elite VSX-90, Samsung 4K K8500, Klipsch Gallery G28's, Klipsch Sub 12, Klipsch RS-52 II, Optik HD cable
Living room- Sony 4K 79XBRX900B, Onkyo RC-360,HTPC, Klipsch Reference R-62II, Rc52II,PS4
Gaming room -Panasonic ST60, PS3, Wii