The FAA document says that they were not confident that the parts were being manufactured in accordance with their approved design. This would not be a paperwork issue. Rather, it is alluding to poor quality manufacturing, poor QC or components not meeting the approved design specs.

It is a rare move for the FAA to shut down a company for multiple products. This didn't happen because of a bad batch of products or subcomponents, in that case the FAA would have made and AD with a specific date or serial number range which would need to be removed from service or inspected.

The avionics guys where I work say that the inside of the AK products have very poor/horrible workmanship.

I feel bad for all of you that have AK ELTs and encoders. It makes me glad that I ended up with an ACK ELT.