You could try putting a couple of load resistors across the indicator terminals. The indicator relays on the older Brutales that didn't come with LED indicators as standard have a self-protection mechanism that trips when it senses too little or too much current being drawn when activated.
I experienced similar problems on both my 2010/2011 Brutales when fitting after market blinkers a while back... only offering up the resistor solution because you've described the problem as resetting itself after you kill the ignition which is what i experienced.
If it was vibration, I would have thought the ignition reset wouldn't have fixed it, but also check your connectors under the dash cover. Sometimes pulling the relay connector off and putting it back might also help things. Hope you get to the bottom of it!
2010 came with LED blinkers. This setup with the integrated tail light was working absolutely fine for years until just recently.. I checked all the connections, they are all in perfect shape. No wire rub-through. No oxidation on the connectors. The flasher relay is meant to deal with LED bulbs. It all works perfectly in the garage with the bike NOT moving. Engine running or off, blinkers work perfect. Brake light on or off the blinkers work perfect. Take it out on the road works for a bit, then nothing. Leads me to think vibration is knocking something momentarily loose. The controller does not reset without the ignition cycle. Works fine again until I start moving and get some vibration, then blinkers stop working.
I was able to give the tail a smack with my hand while in the garage and the blinkers quit working. Cycle power, they work again. Once the control module senses an issue it turns off that circuit it seems. Why MV couldn't just use a regular damn LED blinker control until and circuit design is beyond me.
With the stock tail light and all the rest of the blinkers the same, no issues this weekend. I guess I will open the light housing and see what is what.