Sorry for the late reply.
I believe you've tried different cables as well right?
If this is the case, then the HDD and the connection should be fine. Most probably this is caused by Windows. Disabling these three services that you've mentioned, helped many users that were on Win 8.1.
On Win 10 though, there some other things that could be causing that. Just do some research.
Here are some threads on that(check all the comments and suggestions below):
https://www.reddit.com/r/techsupport/comments/3h4wjg/windows_10_high_disk_usage_100_ive_seen_a_thread/
http://www.tomshardware.co.uk/forum/id-2813275/disk-usage-100.html
I don't think this is a firmware issue. You don't need to update anything.
D_Know_WD