I've noticed with the updated IKTweaks that there is some possible instability/confliction with vrchat IK 2.0. through changing settings and values my body (hip, spine, and arms) seem to vibrate during movements of upper body/lower body while locking to hip, head, or both. I am unsure how to accurately describe this but the best way I can explain is that all movements seem to vibrate the rig bones on the avatar while moving individual parts of your body in FBT. This issues existed for me and some of my friends with using only melon loader 0.5.4, UIX (updated) and IKTweak (updated)
I've noticed with the updated IKTweaks that there is some possible instability/confliction with vrchat IK 2.0. through changing settings and values my body (hip, spine, and arms) seem to vibrate during movements of upper body/lower body while locking to hip, head, or both. I am unsure how to accurately describe this but the best way I can explain is that all movements seem to vibrate the rig bones on the avatar while moving individual parts of your body in FBT. This issues existed for me and some of my friends with using only melon loader 0.5.4, UIX (updated) and IKTweak (updated)