People are always quick to slam a company if things appear to be going bad.
Sometimes a company may start getting much more business than they can handle and things slow down quickly. If they have a small staff it's not always possible to handle the volume of email, snail mail, voice mail etc. in a time that the customer may desire. They could have suffered mechanical issues and are waiting for a mill to get fixed, the machinist could have quit of gotten sick. Maybe a server crashed and they lost email or voice messages. There are any number of legitimate reasons for a company to suddenly get backed up.
I don't know what their situation is so I don't know if this is the case there, it's just hypothetical possibilities. I just notice that people are often not willing to give them the benefit of the doubt (and don't take this personally as I don't know exactly what your situation/arrangement with them is either, just talking generalities here).
And I agree if it they know there are backlogs or problems they should let their customers know even if it's a generic update saying they are sorry but working to resolve the problems because if continues on for too long they will lose business and possibly fail as a result.
I hope that they are able to make things right and resolve their issues.