My keyboard has 2 threaded holes in the bottom that look like they'd be used to attach it to a stand. So...how do I secure it so it doesn't fall off when my dog bumps the stand?

Just add some adhesive Velcro (hook and loop fastener) The industrial rated for 25 pound should be good for most players, 75 pound rated minimum for Jerry Lee Lewis type players.

Set the stand at the height you want, put the hook tape on the stand leg top and then target the fuzzy strip to the piano. Be aware the pound rating is rated per square inch- so you will want to put a 10 or 12 inch strip of fuzzy on the piano, and 1 or 2 inch strips on the stand leg.

I have never seen a carrying case for these offered anyplace... they can be a pain to handle. You MIGHT try to get someone to make a heavy duty cardboard box to carry it in. These are a heavy duty stand... making almost any hard case would triple the weight. They custom make cases for mixers but that type would weigh about 50 pounds for the case alone. If I were making one, I would do it something like the mic/speaker stand cases are with a zipper down the opening. Maybe use canvas... but DO use a heavy zipper... getting the "ears" in and out of a duffle bag would certainly be frustrating to the max.

It sounds like the sustain is stuck on as if a sustain pedal is active. You don't mention if you have one, however if you MIGHT have one and you have used a Roland pedal, that brand is reverse sensed and would cause note to remain on.

Not uncommon problem with boom stands. Some of these have plastic collars with threads... they are for the most part unrepairable. If you need the adjustable function of this, almost anything you do will look like a hack job. If aesthetics are not important, carry a roll of Gaffers Tape. It is black and doesn't leave residue and you can FREEZE the boom at whatever length is good. I know the problem... I have two bad ones myself. I will eventually make some metal collars as I have the necessary tools to do it. Also consider using those hose clamps as locks... not convenient but it will work.

Usually the keyboard sits on top of the X stand held by its own weight. Most of the smaller consumer keyboards do NOT have mounting holes for attaching stands. Piano keyboards that have 88 keys do usually have mounting holes as they are heavier. Most X stands have rubber ends on the tubes where the keyboard sets.

Normally on my stand like this you PULL the knob outward (not turn it) to disengage the pin from the plate with the holes in it... Works quite well and the stand is moree stable than many.

These are sold online at Kraft Music

Yamaha WB53080R Music Rest
Replacement Music Rest for P120, P140, P155, PF500, PF1000

Typically you have to unstring the guitar to get access to the insides.

Use a small miirror to view the insides. You may need to drag the jack out of the sound hole to resolder wires if they are broken. There should be three wires on the jack. One carries the audio, one the ground, and the third connects the battery when the instrument cable is plugged in.

After re-soldering the connections if needed, procure a piece of 1/4 inch wood dowel from your hardware store. Push the dowel through the hole where the jack goes and near the sound hole. Push the jack onto the dowel and then pull it back through the jack hole and pass the nut over the dowel and onto the jack threads and tighten. The extract the dowel rod from the jack.

It is near impossible to reach clear into the guitar body to put the jack back in without the dowel rod unless you have very tiny arms.

Hi there. Search "top hat". There are 2 different depths. Compare measurements to space available in and on the enclosure where you plan to install it. (bottom)
Thanks
Paul

lol....after reading your problem and then posting mine I had an idea. I went to youtube.com and found out that in order to hook up the U CLAMPS...you have to disconnect the table top attachment and connect the U Clamps to the short bases. You then dont need longer screws you use the little black screws that came with the stand. I went to Guitar Center after I did mine and confirmed that theirs was set up the same way....lol...LETS PARTY NOW !! This calls for a celebration party...lol GOOD LUCK AND TEAR THOSE PARTIES UP