Filament Not Sticking and Spraying Everywhere

[gbg444]

Attached photo sums up the problem pretty well. The print starts off great, then after a short period the filament stops sticking and creates a giant mess if it continues to print. Smaller prints seem fine, its longer/larger prints that this happens for. However, even with the parts that print well the filament doesnt seem to adhere to itself very well. Also, if the print keeps going for a while there is a sharp jerking/popping noise that comes from the extruder motor, it happens about every 5 seconds or so, however when I check for grinding there is none present. I feel like I've tried changing just about every setting I can think of but nothing seems to help, has anyone seen this before? Its on a BCN3D Sigma R16 printer.