[Elecraft] APF question

[Mike Weir]

When using the APF function on my K3 I am getting a real tinny sound to the point were it is difficult to understand the code. I was wondering if settings were ok. 
Here is what I do.
1. Zero beat the CW signal with the spot feature and tuning is set to fine.
2. The filter is set at either 400hz or 350hz
3. The APF setting is a .60 I also adjust this setting to see if the audio improves but it does not seem to. 
4. I do try to fine adjust the VFO (fine setting) for the signal to jump out. All that happens is it gets more tinny. 
Any suggestions?
Mike
VE3WDM