The jack for my headphones is to small for the SP-404sx.
Could anyone tell me if they had the same specific problem and how to resolve it? Thank you!

It can be one of two things.

1. Your 404 has write protection on. To turn off the SP write protection press and hold the CANCEL button while powering on. The LCD will say "off".

2. The sd card is write protected. To fix this take out the sd card and flip the little switch on the side of the card.

Figured it out, thanks!

*Edited it new question*

best to create a new thread for new question


you should be able to get the adapter any music or audio or electronics shop,

standard headphones on ipods and stuff are 3.5mm stereo plug, you need a quarter inch (6.35mm) stereo plug adapter