Still problems with external harddrive after sleep although 10.8.5 supplemental update is installed

I am on an iMac 24" late 2007. The external drive is a Hitachi (HGST) Touro 1TB (other drives are fine and never had a problem not even before the supplemental update). Disk utility finds no problems with the HD (had volume repaired never the less).

Is this just my iMac or are others here also still confronted with hd sleep problems after the supplemental update?

Thanks for your input.