Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Amp "rejects" this pre amp

I have a recently purchased Sony STR-DH100 amp/receiver, which I knew would require a phono pre-amp. This Behringer pre-amp (purchased from Musicians Friends) worked fine (no hum) but when I turned my Sony amp up (not very loud)to hear my phono the amp would shut down with a "PROTECT" warning indicating an "irregular current." Obviously incompatible, so I am out the shipping charges to receive and to return the product. What a waste of $$ and time. I am now using my old colege amp (with built in phono pre-amp) to listen to my records.