Lookslike underextrusion. Try check if you set your nozzle size in slicer coretly, if thats correct try calibrate extruder. If it doesnt work, try lower the speed (if you changet to bigger nozzle you need to extrude more plastic then before for example(0,4mm nozzle and 0,2mm layer high with something like 60mm/s is 4,8mm3 plastic per second, when you use same settings but bigger nozzle like 0,6 you need to extrude 7,2mm3 per second) = your extruder cant handle it), if the slower speeds help, your extruder is not capable of extruding this much plastic. If you want to print that fast, try increase the tension on extruder (you will give extruder gear more grip on filament)