I've worked for a lot of different manufacturers in hi fi and pro, large and small. Some of this "ignoring" thing or not answering thing is not intentional. One could look from afar and say "they should do this or do that", but my experience is that manufacturing is a never ending shit show of problems no matter whom you are. Its incredibly difficult to build things and manage all the parts purchasing and subcontracting you must do, chase down the errors that occur, plus also do sales, marketing, shipping, exporting, packaging, plus everything else. Aye yi! Some pick and choose what they can accomplish because they honestly cannot accomplish it all.
So my advice is, if you cannot get an answer from email, call them. For some of the boomers, email can be a very tedious process. Get them on the phone and they respond immediately.
Brad