How are you supposed to make money as a smuggler?

[cgallop]

Can someone help me understand what I'm doing wrong? I've started a few smuggling factions in age of shadows and they all fail in the same way. I build a few mines and freighters and for a few years I start making decent mining and smuggling income to nearby independent colonies. Then for some reason my economy crashes that I can't figure out. My mining and smuggling income drops to near zero. Incidentally, in the meantime my small military fleet is usually trying to control a few nearby independent colonies and I usually manage to get one hidden pirate base built before my economy crashes.

In my last game when this happened it was about 10 years in and I had about 8 mines, 4 mining ships and 20 freighters. There was a smuggling mission to an empire homeworld less than a sector away accepting all goods thanks to me destroying all their mines. I had large stockpiles of most strategic goods due to my mining operations, but my freighters weren't heading to the homeworld. As far as I could tell all they wanted to do was ferry resources from the mines to the spaceport despite it having massive reserves already. I also don't understand why my mining income disappeared, I thought this was supposed to be a steady revenue stream?

Is this working as intended? And if so can someone point out to me what I should be doing differently? It seems like right now it's impossible to succeed as a smuggling pirate faction.