Slow Magic Trackpad response

This is very likely not a BTT issue (not sure I'm willing to live without BTT long enough to test that!), but this forum still seems like a good place to ask about trackpad-related problems. From time to time I experience lags of up to several seconds in pointing and clicking responses from my Magic Trackpad. This makes it quite difficult to hit small pointer targets, to say the least. Up until a few weeks ago I was still running a 2011 MBP, so I just put it down to general system slowness/obsolescence, but now I'm still seeing the same problem with a new Mac mini with a blazing processor and RAM to burn. (iStat Menus confirms that I'm not experiencing CPU or memory constraints.) So what does that leave? Software issues, or a dying Bluetooth transmitter in the trackpad itself?