Windows app upload speed issue


I have been using nextcloud on my local network since version 12 (Now I am on 16.0.5). I have a 1gbps network. Nextcloud is installed as a docker on Openmediavault on Odroid HC2 hardware. Machine has network shares and I can download/upload at the full speeds of around 105 MB/s (appropriate for a gigabit network). However the nextcloud app (also browser upload) only uploads with speeds of up to 12 MB/s. There is clearly a bottleneck somewhere, but I was not able to pinpoint and fix it. Any help the community can lend would be greatly appreciated!