My Yamaha PRS-293 will not play any of the E keys or the Bflat keys. I reset it once (power up while holding the highest note key) which fixed it once. Now it won't fix it. The MIDI plays all of the notes.

Try a master reset to start with.
Turn keyboard off
Turn on whilst holding down highest note on keyboard
Once screen display has complete release key

This will reset to factory settings.
If this doesn't work report back and we can maybe try other solutions.

Dan
Becketts Music Ltd

Water/ moisture damage corrosion of electronic connections or power supply cooked certain chips on motherboeard maybe melted after heating up to much

Hi
The normal reset is to hold down the highest note ( furtherst white key to the right ) at the same time as turning the instrument on. This will initiate a factory reset.

If it was playing fine and just stopped working while you were playing it, it's possible the speaker has failed, or a wire has come off. It is likely something you cannot fix yourself, and should find a local music store, like Guitar Center, who can repair it for you. It's generally not a very expensive repair at all.

If the sound stopped working from one side after you were playing with some controls or editing some voices, you may have set the panning all the way to the right, which would cause no sound to come out of the left speaker. In that case, you would simply need to set the panning to the center again while in editing mode.

If you are not too familiar with the editing features on the PRS 330, and not sure how to set the panning to the center again, you could always simply reset the unit to it's factory settings once again, while will return all the voices, effects, panning, etc. back to like the unit was when it was first taken out of the box and turned on. Here's the process to reset the Yamaha PRS 330 back to it's original settings -

Restoring the default (factory-programmed) settings While holding the C7 key (right-most key on the keyboard), press the power switch to turn the power on.
This operation erases backup data in this instrument (including backup settings in the Function mode) and
restores the factory default settings. The User Songs and the external Songs stored to internal memory will be
retained

None of that works and you do need to have someone look at the unit, here is a link to the Yamaha Authorized Service Locator to find the nearest authorized service center near you -
Servicer Locator

This will be a problem with the key contact sending the wrong velocitiy. To verify, hook it up to a midi source and see if the same thing happens in the connected device. If so, it will need to go into the shop for repair.

You may have turned down the volume internally.
Carry out a factory reset - Hold down top C key (highest note) whilst turning the keyboard on.
Hopefully this will rest everything and it will work again.

Resetting Instructions:
1) Try a partial reset by holding down the last white key while turning the unit ON.
2) If you haven't recorded any performance(s), for a full reset, hold down on the last white key AND THE lst three black keys while turning the unit ON.

My Yamaha P85 had a no sound problem too. I replaced the two 100uf capacitors at locations C216 and C217 on the board where the DC power plug connects. Fixed it right up.

Do an initialization (factory reset) by holding the HIGHEST WHITE key down and turning on the power. Hold the key for an extended time until display confirms initialization complete. This will restore unit to factory defaults.