Do I need to buy a seperate headphone jack adapter in order to put my headphones in? The headphone jack seems too small. If so what should I buy?

Running mixer to receiver??? does the mixer have rca (red & white) audio outputs? if so you can run it that way and hookup to whatever input you want on back of stereo. If it doesn't then you can buy a 1/8" stereo jack to rca and run out of headphone out. (will need a 1/4" headphone adapter though).

Get a
Universal 1/8" to 1/4" Headphone Adapter

use a mini adapter to a large one.(3.5 to 1/4) or mini headphone jack to 1/4 headphone jack.plug a male3.5 into your outgoing headphone jack or from the pc convert the other end of that cord to get you to the proper size or 1/4 head phone jack.the primary cord from the pc needs to be a male to female cord.they make adapters that will get you the rest of the way.3.5 mini male to 1/4 phono female.then you plug your amp in to the 1/4 female.wala

Suspected Faulty PC board Dead Capacitor Or Mod Pot I would suggest returning it for an exchange the problem is your speaker will work on a regular stereo because a stereo powers the sound internally causing the magnets in the speaker to vibrate Headphone jacks are designed to pick up off a seperate circuit board with a different connection to the main board hence the no sound from the speaker.

Some keyboards use the amp output sockets for headphone use.
You might need some adapters for your headphones.
If it fell in, you would see an empty hole. This would be unlikely because it is held on by two screws. If all fails, buy an amp with a headphone jack input. Plug the keyboard into the amp and use the amps jack.

I don't understand your question. The "Aux in" is just that an input that goes to the power amp. Please note that the Fishman Loudbox does NOT have a headphone jack so don't be disappointed as there plain isn't a headphone jack on this unit. I would recommend that you get a small headphone amplifier for the purpose... or even go to a thrift store and get an old stereo system that has a headphone jack and use that.

I have a 250 gfx, and I have had the same problem intermittently, I have concluded that the digital fx section is to blame, as it is also responsible for the speaker modelling for the line/headphone jack, and I have also had problems with my fx section.
If you have anything in the effects loop that boosts signal volume remove it, a small boost in the loop gives the power amp in these a nice glassy sound, but seems to be (in my case at least) responsible for the failure of the fx/ emulated line out.
Also check all your leads and headphones cord, try some different headphones if you have them.

It is NOT likely the keyboard is "killing the speakers"... OR the headphones for that matter.

I suspect the problem is bad switch contacts in the headphone jack that cut off the speaker line outputs when headphones are plugged into the pro keys. These jacks are, to put it bluntly, JUNK... they are EASILY damaged by pulling the cable plugged into them sideways. You will need to service the unit.

There are many models of Marshal amps icluding 15Watt types.

First thing to try is to see if headphones have normal volume. If they do, then the headphone jack switch that connects the speaker is LIKELY bad.

If the headphones do not have any volume, LIKELY causes are:

1. Fried output power amp

2. Volume pot is broken or has bad solder joints to the circuit board.

hi there headphone jacks usually only come in 2 sizes, an obviously large one or a small one, (the headphone and the microphone jacks on your computer will be the small ones) if you have a favorite set of phones with a small jack and you need the large one you can buy an adapter that fits the large jack when you plug the small one in. good luck