"He who marches out of step hears another drum." ~ Ken Kesey
Could just be a weak breaker or loose connection. Personally I would tighten all the connections first, no cure swap breakers before go looking for something else.
The key to troubleshooting this type of issue is the use of a clamp-on-ammeter. It will tell you exactly what the amp draw is and if that exceeds your breaker rating.Here's my favorite troubleshooting tool.http://www.fluke.com/Fluke/usen/Electrical-Test-Tools/Electrical-Testers/Fluke-T5.htm?PID=55986&trck=t5Some day I'll post a video about using it.I bet there's several on YouTube already.
I,m beating its weak wires over time or a connection needs tighten...your getting an arc somewhere in your lines hope you get all fixed.Darryl
Connections. We all know how you like to half-@ass things. Actually, it could be that, how hot is your panel getting? Ours would always trip when we running a lot of juice at once. The panel would almost be too hot to handle.
power cut of course.