Just did my first couple of prints from a roll I got from Filastruder. The parts are very brittle. I can easily break a fairly sizeable structural part with my fingers. Same part printed in PLA, PLA/PHA, and PETG I cannot break without pliers. I'm printing at the recommended 80c bed and 240c nozzle. Using E3Dv6 hotend with .3mm nozzle pushed by a Titan onto PEI over glass print surface. No adhesion issues. 30% infill. The part visually looks very good. Anything I should try to resolve the issue? Is it possible I got a spool from a bad batch or something?