[Dubdub]

If you read through the 900 section and a couple others, you will see a similar theme. Some of the 9900 just weren't put together that well.

However, given the problems you shared, those are more indicative of water or dropping the device causing the problem. Not to say that caused it, just saying that dropping and water causes those types of problems.

Also, running the battery down past 20% on a regular/frequent basis will damage the battery (on any lithium powered device, not just the 9900) and requiring it to be replaced.