WD MBL DUO streaming and copying soooooooo slow

Hi everybody :) 

I bought a new WD My Book Live Duo 6Tb to store Full HD videos  in it and watch them by streaming in my Laptop or Tablet.

I had a D-Link N300 (10/100) as a router, so my transfer speed was 1Mb/s (wireless) , 10Mb/s (wired) and streaming HD videos was not fluet at all

so, to have the best result,  i bought an ASUS RT-AC66U ( i know it’s not a WD, but it is number 1 in most of Top10 Routers ) , however my transfer speed became 640 kb/s and streaming was sloooooow . 

My Internet speed is 25 MB/s ( optical fiber) 

The ASUS RT-AC66U 's data rate :   -802.11b is up to 11 Mbps  

                                                                 -802.11a/g up to 54 Mbps

                                                                 -802.11n (2.4 GHz) up to 450 Mbps

                                                                 -802.11ac (5 GHz) up to 1.3 Gbps

My Laptop ( Dell Inspiron N5110 i7 )  supports 802.11b , 802.11g and 802.11n

The Question is : Is this equipment   enough to have a fluent streaming of my Full HD videos stored in the MBLD ?

                                Does it enable me to copy my files faster than before?

                                or the MBLD needs another equipment to have optimal performance ( such as my net ac1300) ? 

                             Thank you for helping me :) 

The internet speed should not affect the local transfer rate. Have you tried using another Ethernet cable? Also check the link below for some steps you can try. 


thank you very much :)