Turris as a nas slows over time - with new Ubuntu


#1

I have turris omnia NAS version with 2x4TB disk. btrfs in RAID1. I have some issues with setup system - raid was setup using mkfs.btrfs. But it stabilize and I get read speed for large files around 70-80 MB/sec. Which was totally fine. Disk is shared as samba via standard LuCi interface.
One I upgrade my home computer to Ubuntu 18.04 I notice drop in performance - to several KB/sec which could be solved by rebooting turris. I’m still not certain but the drop seems to impact only my ubuntu machine - I have another desktop on Windows 10 and it seems to be working fine.
NAS do not show any extra load and problems starts immediately after loading file - primarily videos played with ubuntu internal player - same problem is with VLC.
Main question is was there some change related with unbuntu upgrade from previous LTS to new LTS ?