Chony,

If the proble is the leaf-switch contacts within the headphone jack, then clearning it with cotton swabs and canned air will not correct this problem because the swabs cannot get between the switch contacts.

If the headphone output and normal stereo output is working just fine, then the problem may be one of the headphone jack's leaf switches. The only way to check this out is to open the keyboard, then connect a small jumper to the switch, thus bypassing the contacts. If this activates the speakers, then the problem can readily be solved by replacing the headphone jack. This type of jack is available at most electronics stores for under $3.

Gary