[Elecraft] AF1 Audio Filter Question

[Paul Clay]

Just completed building an (external) AF1 audio filter mini module (Rev A board that required the cutting of a solder trace on the AF input and the addition of a jumper on the AF output).  Works great except, I've noticed two things I'm curious about:

1.  With stereo headphones plugged in, one the audio in one channel is noticeably louder than the audio in the other channel.

2.  If I plug a speaker in with a monoral 1/8" plug all the way, I get audio out but the volume is low and there's some significant distortion in the audio output; BUT, if I insert the plug in just part way, I get lots of volume and no distortion.

Wonder what might be causing this?  Wouldn't think much of item two (figure I should just be using a stereo plug to connect my speaker), but the presence of the distortion and the lack of balance when using my stereo headphones makes me wonder if maybe the LM386 chip might be damaged.

- Paul N6LQ