Geeetech Prusa i3 Extruder seems to push more filament, gear slips/skips?
A nozzle with a nozzle width of 0.3 mm cannot print a 0.3 mm layer height. You could do that but you should not as you ultimately pay the price in the form of a less aesthetic finish. The general rule of thumb is to maximize the layer height at 75 % of the nozzle width, so a 0.3 mm nozzle would allow for a maximum of 0.225 mm. The rationale is that the filament leaves the nozzle as a tube and needs to be flattened to make it flat and adhere to the previous layer, too high layer heights increase the pressure in the nozzle (more filament is needed) causing a less than ideal extrusion and cause the extruder to skip; this is identified by observing a distinct clicking noise.

Please lower your layer height (try 0.2 mm) and decrease the printing speed to see if this works better.

Furthermore, for PLA, temperatures for the hotend (unless you have some sort of a special PLA filament) and the bed temperature are too high. Please aim to print PLA at about 200 &deg;C with a bed temperature of 50 - 60 &deg;C.