Maas 2.8.X disable sndfile on in nginx, how

Hi, I have maas deployed and am trying to deploy a bundle. everything works as expected, except the pxe boot is beyond slow. the root.tmp.img takes 15 minutes to fetch from the maas server.
I think it may have either something to do with sendfile on; in maas nginx or the MTU differenmce. the maas server has mtu 1500 and the nodes are booting with 9000 … however, setting it back to 1500 on both, had no effect.
Every time i disable sendfile on; in /var/snap/maas/http/nginx.conf it is restored ton ON. How can i disable this?
Thank you already for your time and effort :smiley: