Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: Hard to figure out

I have owned several of these types of product from Motorola and Jabra. This model from Parrot is really hard to figure out without studying the manual. Two examples -- the huge knob on the front of the unit does not adjust the volume during a call, and there is no obvious way to kick off the iPhone/Siri recognition engine. It seems like this thing is just grossly over-engineered, to the detriment of the normal or casual user.