One of the many reasons I feel why Buffalo is getting delayed is their constant asking for additional information.
A. They ask for documents that are not mentioned in the list initially. For example, they ask for copies of employment contacts and letters from supervisors attesting to the applicant's employment history. We send these documents. Then they ask for W2 (tax returns) for all years worked in the US.
B. They take longer than usual for initial processing. During this time, our FBI clearances (which I believe Buffalo considers valid only for one year from the day the clearance was issued) expire. Buffalo asks for an updated FBI clearance, which adds another 2-3 months to the processing. Back and forth with receiving documents, sending them, the consulate getting them and acting on them takes out around 6 months easily.
A possible solution to this problem: Send ALL documents related to employment , educational qualifications, civil status, etc that you have even if the visa office does not ask/need them initially. This saves considerable time. What happens in this instance is that if they do not need the documents they will trash them, no harm done here; but if they need to see those documents and they are present with the file, your time is saved!
Just a suggestion.