I have always wanted to know, do alpine borders (hard boot) ever complain about heelside chatters?
YES, big time... So it's not just my angles. Although that could contribute but I'm going to take Snowolfs advice and leave the angles alone for now.
There are multiple threads on a hardbooter forum and the general advice seems to be to focus on getting your weight over the tip on corner entry as much as possible.
What worked for me yesterday was being mindful of my weight, and exaggerating bending my knees even more than I usually do. If I really want to rail a heelside corner I'm entering on the nose, then bending the shit out of my knees and pressing through the turn.
Was putting so much energy into the board I saw my tracks and there was a couple feet between each carve where I wasn't touching the snow at all...