Problem with yamaha P95 Keyborad
I'm having an issue with my Yamaha P95. Some keys blast very loud without even touching them when playing some chords. I've been facing this problem for 1 week now. I only bought the piano 3 weeks ago second hand and the first 2 weeks everything was working perfectly fine. I tried to clean all the dust inside the piano but I can't really open the top and reach under the keys. I dont really know if the dust is even a problem or maybe the moist and cold Sydney air. One thing I noticed is that under the keys the is a very creamy texure sticking, almost like vaseline. I really need help as I cant play at all like this. Any assist would be highly appreciated.
Here the problem:
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