There will always be complaints about players being too loud, and
too soft.

Without fail, it is the musically illiterate who are the biggest
complainers about music being too loud.  (Of course, it is too loud
because they want to talk during the music and be heard!)   Okay, set
the volume level so you have a mush box of some sort of sound unlike
anyone who ever played the piano well.  The customer is always right.
Set the volume like they want it, and hope you never have to listen to
it!

Too soft!  Other than major leaks in a player causing it to miss notes
and play too softly.  I once had a customer who was hard of hearing.
He insisted his Duo-Art was playing too softly, even in the "dance"
mode.  In desperation, I tied both accordion pneumatics down, which
raised the volume to unreasonable level and no expression.  He thought
this was great!  This was the only way in which he was satisfied!

One more!  Another partially deaf person complained that the top six
notes of her piano had no sound at all.  I tried them and found them to
be fine.  I notice that she was wearing a hearing aid, and concluded
that her hearing loss was severe enough that she could not hear high
frequencies.  It was quite difficult to tell her tactfully that her
hearing loss was the problem, not the piano.

Bruce Clark