External drives very slow

[jcxh]

Both my external USB 3 drive that used to be >100Mbs and my external NAS 125Mbs are drastically slower ~35Mbps after I upgraded to Yosemite - it can't be a hardware issue affecting two different drives - I have a late 2012 iMac 3.4Ghz i7 and 16Gb ram so my local machine isn't the problem. And my connectivity from an ancient XP laptop is faster to my NAS - Apple - what have you done?

 

[simonsi]

Is Spotlight still indexing them?

 

[jcxh]

NAS isn't spot light indexed and external USB drive is already indexed. People should use Blackmagic speed test and see if they are also affected.

 

[VanQuocTuan]

Me too.
my mbp not index my external hard drive. What should i do now !