Im running into trouble, when connecting to my NAS through SMB:
Windows 11 to TS-431XU with QTS 5.2.3.3006 Build 20250108
They are connected through 10GbE Links with a Unifi Switch inbetween.
Reads are 500-800MBps, so hardware seems to be fine. 4 HGST HUH721212ALE604 Disks in RAID5 SSD cached.
I had the issue also with downloads. But after deactivating SMB Signing, the download speed increased dramatically, but the upload still faces 14-15MBps.