delayed response from magic trackpad 2

Most of the time, the delayed response happens when I am moving cursor with one finger. It's as if I have to "wake up" the mouse by wiggling my finger all around and it will grab the cursor again. Rarely has a delayed response when scrolling with two fingers.

I am using El Capitan with my 27" iMac. Sometimes wireless keyboard, sometimes full size wired keyboard. Doesn't seem to matter which keyboard I use so I don't think it's another device interefering with the bluetooth connection.

On a side not, my old trackpad won't connect with my iMac at all.

Anybody else?