Prima facie, the problem seems to be either with the extruder or the filament. It might be that the extruder is getting clogged due to various elements such as dirt or contaminants in the filament itself. This can be solved by clearing the obstructions from time to time. Another reason could be excessive nozzle temperature. With higher than prescribed temperature for the filament, if the filament stays for a longer time in the extruder, the filament tends to burn causing obstruction in the nozzle. A combination of using good quality filament, setting the right nozzle temperature along with frequent cleaning of the nozzle should help you in printing smoothly.
If none of these solutions help, then you might contemplate changing the extruder head which is highly unlikely.