NAS transfer speed really slow

Hello,

I have a MBP early 2015 running on Big Sur and im trying to improve performance for file transfer between this MBP and a NAS. Currently, I can't even play a 1.5go video from the NAS on my MBP without lagging a lot. A disk speed test app show my download around 5-7mo/sec and upload around 0.5 mo/sec.

My NAS is a buffalo LS210 2To and is connected to my wifi rooter via ethernet connection. The internet speed test show me a 300mo/sec upload and download and no other device never had wifi speed problem.

I acces my NAS via the finder network and my NAS is set for a SMB connection and the DLNA is enabled too. when I checked the smbutil command, it showed me that SMB 1-2-3 seems ok but im not sure but I thinks its running on SMB-2.

I checked a lot of forum thread about this but nothing worked yet.
I also tried to change my tcp.delayed_ack from 3 to 0 and it didn't changed nothing.

My question is : Is there a way I can configure my network differently so I can normalize the speed connection between my MBP and my NAS ?

Thanks for your help and if you need anymore info to resolve my problem, im willing to share it for sure !

Simon
NAS transfer speed really slow
 
 
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