Trouble with Yamaha P-120

[anapollosun]

Hey Guys,

I have a yamaha p-120 piano with an issue in the 1/4" out connection. It works when I plug it into guitar amps, however, I only get feedback when plugging into my MobilePre external sound card. This hasn't always been the case. When I first got the piano it worked in both. It doesn't seem like it should be a defective connector, because it wouldnt work in both. Also, I know my MobilePre works, because I have plugged mic's, guitars, e-drums into it with no problem. Please help.

Thanks,

David

[quantum]

Welcome to Pianostreet,

First of all, I wouldn't recommend plugging a keyboard into a guitar amp as you could damage the amp.  Guitar amps are not designed for the frequency range output by a keyboard.  Use a proper keyboard amp. 

Try swapping cables, and see if you get different symptoms.

Check your audio routing in software.  You could be feeding from another source.  Eg: Make sure your computer mic isn't selected as an input. 

Make sure you are using the correct sound device and drivers in your software.  When you use an external sound card, remember your computer likely also has an internal sound card.  That means there are at least two sound devices to select from.

While troubleshooting, make changes only one at a time, then evaluate the results.  Repeat until you have found the culprit.  Don't try to change 5 things at the same time in order to get over it quicker.