Slow Configuration even within the same HDD

My Raid1 8TB MyCloudEX2Ultra is extremely slow. First I thought about my home network and issues with that but even if i try to copy a file within the cloud, from one folder to another (for example from public to smartware) the transfer speed drops to ca. 3 MB/s so the file of 860 MB takes at least 5 Minutes. I tried all the test possibilities and it is always saying everything is fine, but that’s not true something must be broken!! What should be the normal speed for such a transfer I think at least 100 MB/s
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@harocas You have placed your topic in the My Cloud Home sub-forum, you may want to post it in one of these, https://community.wd.com/c/network-attached-storage .