This is my second personal Keurig and I have several friends and family who have Keurigs Mine is noisy (when brewing) and none of the others I have experienced are this noisy what can I do? It works fine - just is noisy enough so that if someone is still sleeping in the house I am hesitant to brew a cup of coffee for fear of waking them

SOURCE: Keurig B50 Ultra brewer

This is a known problem with the B50 which Keurig will acknowledge if you press them hard. Some users have suggested trying to clean the check valve just inside the water outlet but the best solution is probably to call customer support, complain like crazy, and take the discount on a new machine that they will offer you. Apparently, this problem occurs much more often with the B50 than with more recent models, which may explain why it isn't on the market anymore.

SOURCE: Keurig starts & stops without brewing coffee, just descaled

The pic is clogged with coffee or the air bladder is bad. Use the tool on the underside of the tray to clean out pic. If that doesn't work, the bladder will be bad.

SOURCE: My Keurig B70 at our home in Maine worked fine

sure it need descaling & cleaning

SOURCE: My Keurig coffee maker is not brewing the size cup

Hello. I recommend that you descale your machine. Here is how to do it: http://www.keurig.com/help/De-scaling_instructions.pdf?mscsid=27SCSLLH993M9P2RCE7EGD5S1AK660A1

Please reate my answer as very helpful. Thank you. Joe

SOURCE: Keurig Platinum shuts off after one brew. Will

I came up with a very simple workaround to fix this issue:
http://www.nate-lewis.com/blog/?p=288

The problem is with the water tank not having a proper seal to the brewing unit.