My embroidery machine has started bird nesting

[Shrubber]

Hi. I'm new to embroidery and I've been lurking here for a while and picking up tips and currently just getting familiar with my new Brother M280D. Its been working fine but suddenly and without any interference from me, its started to tangle the upper thread under the footplate cover. I havnt adjusted the material or the tension or thread. It makes a banging noise then starts squealing and the frame stops and carries on sewing until I shut it down. I have to cut away the material to get the piece back out of the machine and then unscrew the plate to clear out the mess underneath. I'm left with a huge tangle of upper thread tangled around the feed dogs and bobbin case. When I start embroidering, the the thread will constantly break and then after a few seconds of sewing it'll jam up. I've changed the bobbin, made sure bobbin and upper thread are threaded correctly and cleaned out the bobbin case. Same material, same needle and same tension. I'm completely at a loss as to why this is happening and why it would suddenly happen. I literally came back the next day and started where I left off and it started to happen.

Anyone have any ideas?