Trackpad sometimes won't switch on

I have an intermittent fault with my trackpad.

Sometimes it just won't turn on. Or sometimes it's working one moment and then just dies.

And any combination of replacing batteries, turning the MacBook Wi-Fi on/off, attempting to Power on the trackpad just won't do anything.

And then 10 minutes later when I'm doing something completely different, the green light just comes on and "trackpad connected" appears on my screen and I'm good to go again.

Is it a faulty unit? Is there some firmware bug?

Does anyone have any idea for fixing it?

PS how about tags for faulty, intermittent-fault?