Same issue. Disks won't go into hibernation anymore. When I disable BTSync the problem goes away. Synology DS1512+
I'm having the same problem with my Synology NAS. Since installing BTsync, my HDDs no longer go into deep sleep and hibernate anymore. It's rather frustrating. I've decided to disabled BTsync and stop using it until this issue is resolved. Are the developers confident the problem will be fixed in 1.4? Is there any news in regards to this?