ShivaHaze

Hey everybody! I own an Anycubic Cobra Max as 3D Printer. The first while is printed really well out of the box but now I am experiencing sudden printing problems and I am not sure what exactly could be the cause. I have printed two heat-test towers going from 180° up to 225° in 5° steps. The white tower is PET. The black tower is PLA. As you can see I have a strong stringing problem and the texture at some spots is quite grainy too. Is there anything you guys could point out for me? Any tips or hints? If you need any further information please let me know and I will give my best to provide everything needed. 🙂 Thanks alot in advance! Cheerz!