I have play MKV 720P files thats connected directly from my 3.5" Ext HDD to SAMSUMG Bluray player. Everything run perfectly. However its not work well with 1080P format. The movie is lagging. Is there any better way of playing MKV 1080P file?

I was thinking if the USB cable is insufficient power to carry such larger data.. How fast data transfer rate does it require? How much its capable of? The player can play BD 1080p well.. How to solve this problem as I am trying to cut cost buying the BD... I am now practicing a share policies where my colleagues and I exchange the mkv..