Microsoft has confirmed to MCV that the disc read error introduced to some consoles by the upcoming firmware update is not specific to certain types of Xbox 360.
Yesterday it was confirmed that any users whose consoles suffer as a result of the update will see their machines replaced with a new Xbox 360 S 250GB for free.
Following a recent update to our system software, we have become aware of an issue that is preventing a very small number of Xbox 360 owners from playing retail game discs. This issue manifests itself as a unique disc unreadable” or disc unsupported” error on the screen and is unrelated to our recent public beta.
"This disc read error message is tied to a change in the disc reading algorithms in a recent software update and is not specific to older or newer versions of Xbox 360.
"We are also able to detect this issue over Xbox LIVE and are proactively reaching out to customers that may be impacted to replace their console. Any Xbox 360 owners receiving this error are encouraged to contact us at www.xbox.com/support/contact so we can verify if the console has been impacted."