Phil Keller wrote:

> My original design had the PIC ground and the analog ground connected 
> together.  THEN I read the specification for the player and it says 
> "Analog return - Signal, never to be grounded inside attached device."  
> I do not have access to the internals of the device 

Are you going to power your circuit from the same power source as the MP3
player? Can't you open it and take a peek? Mostly the analog section is not
that complex. This phrase doesn't necessarily mean that you can't connect
the two grounds, if I understand it correctly (without its context). 

Can you at least look at the output with a scope -- referenced to the MP3
output ground? A capacitor (to block any DC) and two resistors (to bias the
AC at half the supply voltage) may be all you need.

Gerhard
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