[Closed] Grease or bearing / stud lock for integrated headsets?

My Trek 1.5 has an integrated headset where the bearings sit directly on machined surfaces in the head tube (i.e. no separate press fitted cups).

There's quite a lot of creaking coming from the front end which I'm presuming is partly coming from the headset. All the surfaces are bone dry / slightly corroded.

As a possible solution to the creaking, should I grease the frame cups (I know I probably shouldn't) or should I use some bearing fit or stud lock - since they're somewhat looser than what I would describe as 'press fit'.

So grease or studlock? Or try something else?