[kefalo81]

Hi
I reacently finished my cmoy, made my own pcb according to the http://williamneo.blogspot.com/2008/01/diy-cmoy-headphone-amplifier-for.html, and after testing it I discovered that it works fine for two or three seconds,and then starts to distort, and when i turn it of an on, it improves to be good,but sometimes it it works fine for whole 5 minutes and then go bad.Also by extracting my 3.5mm jack(out) to the half it stop with distortion. What can be cause of distortion?

 

[nikongod]

Have you done the tests suggested by Tangent in his troubleshooting article? 
What were your results? 
 
For clarity copy and paste the whole article into your reply, and type your answers in red. 

 

[tangent]

Have you tried changing the battery?
 
A near-dead 9V battery can give this behavior.
 
My troubleshooting article is here.

 

[duncan1]

If by turning it on and off sometimes cures it for 5/10 minutes then it sounds like a high resistance soldered joint in the power feed from the battery to the chip-[-the surge of higher current overcomes the the high resistance for a while] If not it still sounds like a dry soldered  joint somewhere. .In a dual chip positive is pin 8 negative pin 4 so when it distorts measure the voltage across those pins . If it is a simple splitter[no twin rail power chip] then 4.5 Volts +/- across it.[total 9 Volts] .Try that first. 

 

[kefalo81]

solved