LED signal light issues.

Hey got a question. I replaced all my incandescent (from dash and interior to brake and side markers) to LED and put in the LED canisters for turn and hazard. All work fine but the front turn. When headlights are off the front work fine, when headlights are on front wont flash but back do. There is no "light out" indication on dash or "hyperflashing". Will load resistors work for the front? In other words with all LED but front turn lights work when headlights are on. It almost seems like the flash voltage is less with headlights on. Do I need to add a relay in for the turn signals to get them to work with LED's?