My Book Live suddenly slow

The My Book Live in my network (Gb) has slowed to a crawl. It fluctuates between mere 10s of KB/s to at most 3 MB/s. It would previously move data in the range of 10s of MB/s (I think I had seen 30 MB/s at least). Is something happening? Granted, it’s pretty full. 9 GB out of 2TB left. Is this the problem?

Any idea? Twonky maybe?

Empty space it was. Deleting some stuff to about 13 GB helped and brought the transfer rates back to normal. So the threshold may be around 10 GB. I then went on a cleanup spree and am around 40 gig free, and still going.