https://m.youtube.com/watch?v=gwb4po8vrLw
Part 1 and 2 of this video worked for me. Had the same problem with a couple keys. I went through every action part(as shown in the video) and lubricated each part with a Naptha/silicon solution. Then gently expanded the bushing holes underneath each key. Also libricated each metal bushing with a fine household oil. Took around 5 hours total but each key's action is perfect.
Part 1 and 2 of this video worked for me. Had the same problem with a couple keys. I went through every action part(as shown in the video) and lubricated each part with a Naptha/silicon solution. Then gently expanded the bushing holes underneath each key. Also libricated each metal bushing with a fine household oil. Took around 5 hours total but each key's action is perfect.