XM loses it’s mind at startup

The infotainment system in the 4th gen is very unstable. I was having issues with the XM much like yourself, and ended up canceling the XM because of it and started using podcasts and playlists on my iPhone. Until, my infotainment system started to restart randomly, most times when a phone call would come in while listening to music. At first it was only once or twice a week, then it started happening daily. I finally replaced my head unit with a Alpine DDX-9904S and haven't looked back. I've had zero issue since then. I'm sure a software update will fix most problems eventually, but as I am in my car for 4 to 5 hours a day, I could not wait months for Toyota to figure out the issue and update the firmware. I now have Apple CarPlay and Android Auto and couldn't be more happy. Probably not the solution you were wanting to hear, but even consumer reports notes that the infotainment system on the 4th gen is buggy and unreliable. Luckily, its the only problem I've had with the car. Love everything else about it.