I’ve actually been noticing this too lately. I have a 4TB MyCloud.
I’m still doing some testing, but it seems every time I connect the drive to the router speeds start dropping until they reach about 1d /1u.
A simple reset on the modem and router at this point wasn’t doing anything, but while trying to diagnose I unplugged everything and it was stable for two days. At which point I reconnected the MyCloud and within a couple hours the speeds dropped back to 1d/1u. I’m not doing any transfers to or from the drive during this point in time, it just seems to drop off.
I recalled that when I first set it up I didn’t use the cloud feature to allow me to access the drive outside of my network and that around the time that I activated that feature is about the same time that the problem started to happen.
I’m currently testing to see if there is anymore to this idea. So last night I disconnected the drive, rebooted my modem and router, checked that the speeds were back up, then hooked the drive backup, went to the settings and disabled the cloud service.
I’ll check the speeds when I get home today and for the next couple days to see if things still slow down or not.
This actually makes me wonder about something I thought about when I was purchasing the MyCloud drive, which was why I needed a login setup through the WD website to access my drive. Like is this strictly some kind of proxy or vpn connection to get to my drive, or are my files or even some part of my files being uploaded to a server without my knowledge?