In an admirably thorough and even-handed way, Mobile-review.com has investigated the 5800's earpiece problem to find its cause, and they've also got a lengthy official response from Nokia detailing what went wrong and how they've fixed it. In short, the cause was humidity gradually getting inside flawed earpieces. Nokia changed earpiece suppliers in late January so that 5800s made in February 2009 and later should be okay. Anyone with an older 5800 can get their old earpiece replaced with the new version at an authorised service centre. If you're unsure when your 5800 was made, the service centre should be able to tell you over the phone using your IMEI number.