My amp won't play sound without headphones plugged in

COntact Peavey for the manual and suggestions as to setup. Here's their link
Peavey com

http://www.peavey.com/products/vypyr/

about 3/4 down the page

Call Peavey Customer Srervice at 877-732-8391 and they'll email it to you.

Sounds like you blew a fuse. You should locate the fuse and replace it. It might just be the fuse, but fuses usually when something's very wrong.
Try replacing the fuse.You might be lucky.

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

Have you tried requesting from Peavey directly? [email protected]

The voice coil on the cube speakers must be scraping against the magnet.Or the speaker cone must be damaged causing it to flutter at low frequency where there will be large cone movement. Try removing the phono jack from your musical instrument/ guitar and touch the tip of the jack with your finger. You will hear a hum, now turn down the volume and listen to the speakers very closely and see if you can identify the flutter. All the same you will have to fix the speaker or replace it. Have you ever dropped the speakers, if so the speaker frame could have warped causing the scraping noise.

it sounds like an input jack or plug problem, first clean them with alcohol. try and clean the jack with a Q tip and alcohol.

Suspect switch contacts that are a part of the headphone jack.

I have heard this problem occurs often with the vypyr I have heard to try and turn it oun without your guitar cable plugged in and it should work fine. If not try wiggling the guitar cable out a little and and should turn on and try and get the update for it.