Instruct: Classify a review into positive or negative sentiment.
Query: Disappointment with This Sherwood, Praise for Amazon

I recently tried 3 times this Sherwood model. It too often shut off by itself. Maybe from a circuit breaker inside it, or from poorly manufactured press-buttons on it, or from an electrical problem where I live. I plugged the unit into different sockets, and the problem persisted.I have the same model that I bought years ago, functioning well in the bedroom. I also have that model at a house in Florida, without it shutting off.Amazon was surprisingly fast in replacing the receiver with the same receiver at my New York City apartment, within the return period, without hesitation. The problem continued. Again, maybe the problem is related to circuitry in the apartment. The Sherwood and an earlier, older Onkyo receiver continue to have similar problems, where some of the buttons suddenly fail.