ThinkPad X270 touchpad

After all Haiku runs pretty fine on my “new” X270. But just the touchpad/trackpoint-combo is driving me crazy: Sometimes only the trackpoint is working, sometimes only the touchpad is working partly, sometimes both are working and on rare occations no one at all.

The mechanical switch behind the touchpad did’nt show any life at all and activating the virtual click/tap on the touchpad is totally hit and miss with a chance of 10% (Of course i’ve double checked the hardware with Linux.) Any idea how to trace and debug this problem?