I have just bought a ryobi 125mm angle grinder and returned the 110 mm one I had just purchased because it was stopping regularly as is my new 125 mm one I now think it might be a battery problem I have 4x5 amph batteries two 6 amp and one 2 amp .I run my 18 volt ryobi lawnmower blower and my vacuum two ryobi drills and a circular saw. All ryobi the angle grinder is the only tool that cuts on and off the other tools run as normal what can be the problem with the angle grinder