I feel that a lot of reviews are fake - and not just for audio and video equipment. There are so many affiliate sites out there on which people write reviews with links to products on Amazon and other seller sites. They're fishing for a sale so their reviews are going to be biased to the positive.
I have a friend who has an affiliate site for beauty products and she's told me that she throws in a negative review every now and then. She also rarely tests the products that she reviews.