I’d hold of vacuuming during a roast (just as a best practice) and to avoid introducing any additional load on the Bullet’s source outlet.
That blinking red LED still interests me and I’m wondering if you have always used the vacuum while roasting (even back when your Bullet was working properly)? Is the Red blinking LED a new thing that just started when the heating problem began? If you noticed, was that LED green back when the Bullet was working properly in the past?
If the blinking Red LED is still happening (without the vacuum involved) along with losing heat as your test video shows, it could be a designed status indicator of what is wrong. There are LEDs that are dual color depending upon the input driving them, so maybe “Green” means OK and “Red” (blinking) indicates a fault. Without any schematics or a technical manual on the Bullet, I’d be guessing at the purpose of Red (blinking) LED on your unit vs the Green (solid on) LED on my unit.
One thing to consider about power outlets is what else may be sharing a given power line with the Bullet. In my case, I installed the 20amp line in my shop that I use for my Bullet. Because of that, I know that there is nothing else in the house that shares or will impact that particular run from the breaker. have you tried running the Bullet (just a test run without beans) from a different outlet that is not on the same breaker as the outlet you have been using?
This may just turn out to just be a new failure in your Bullet. But without some interaction from the Aillio team, we are just playing with various ideas.