Apple also pulled documents regarding slow performance when using multiple Bluetooth accessories, as well as a workaround for flaky routers that wouldn’t cooperate with Remote Disc. If users are experiencing difficulties with Remote Disc, Apple had recommended updating the firmware on the router in question. Boot Camp installs require the use of a USB optical drive, and will not function with Remote Disk. Apple cautioned users that they should "be sure to connect [their] external USB optical drive to [the] MacBook Air before starting the Boot Camp Assistant." Users who wish to use headphones must pay attention to the size of the connector, as Apple has warned that some connectors may be too large to use due to the foldout door. A headphone extension cable can be purchased to remedy the problem, which Apple sells through its stores. Running the migration utility over Airport was also not recommended, rather that users should buy the USB Ethernet connector and perform the operation with the adaptor. Users that insist on doing the migration over wireless, they are advised to ensure that the Airport signal strength is high before beginning, as a drop in signal could result in data loss or corruption. Apple also advised users that were suffering from stuttering video when using the built-in iSight to upgrade to Quicktime 7.4 to remedy the problem. In the event of overheating, the MacBook Air is designed to reduce the clock speed of the processors, which can be remedied by using the Air on a cooling pad to dissipate the heat. Apple has not commented on why the documents were removed. MacNN recently had a chance to unbox and test a MacBook Air, while iFixit was able to disassemble one completely. Primate Labs performed a benchmark of both the 1.6GHz and 1.8GHz models, comparing both to a 2GHz MacBook.