Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Disappointing

I received a set of speakers which functioned perfectly for about two hours and then stopped working. Harman Kardon customer service replaced this set with one containing a subwoofer which cuts out and a non-functional left speaker connection.I am attempting to get another replacement set now. The manufacturer has not called me back, and I have no idea if they will replace the set if they do call.The whole situation is sad because I really like the way these speakers are designed, and I enjoyed the ones which worked before they unexpectedly shut down.