Hey Guys, I have this persistent homing issue where my OX/ TinyG does this

Hey Guys, I have this persistent homing issue where my OX/ TinyG does this sort of “blip” in Y Axis travel. It doesn’t actually stop, but a very quick stop-go type of thing within the first second of y travel. If it hits the y limit switch before doing this blip, it crashes out, but if it has enough distance to do the blip prior to the limit switch, no problems.
Has anybody heard of this or experienced this? I have done quite a bit of work to make sure that there is no noise interference in any lines, and the machine runs fine otherwise. It seems inconsistent with a wiring/noise issue. Perhaps it is to do with machine acceleration control settings or something?
Thanks