I have changed the AP to have a management VLAN and the results are as I stated.  Traffic is duplicated, but half of it is tagged and half is untagged.  Without a native VLAN, it ends up on VLAN 1, as expected:

switch#show mac address-table dynamic interface gig1/0/8
          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
 100    9c76.13d8.3131    DYNAMIC     Gi1/0/8
 100    d436.398f.7944    DYNAMIC     Gi1/0/8
 100    d44d.a417.4052    DYNAMIC     Gi1/0/8
   1    4052.8100.0064    DYNAMIC     Gi1/0/8
   1    d44d.a417.4052    DYNAMIC     Gi1/0/8
 600    1c61.b4cc.6764    DYNAMIC     Gi1/0/8         # This is the MAC of the access point

I am frustrated.  I really want to use this AP.  Is it possible there is a hardware issue with my access point?  Is there something in the CLI I can do to further my troubleshooting?

  @Tyrade 

Hi, I agree with @shberge, from my knowledge, the current mechanism of the EAP is to send messages to two layers at the same time, one is to send management information to the management VLAN, and the other is to send the wireless client's Internet traffic information to the current VLAN based on the data layer.

It is recommended that if you are using a non-Omada switch, to prevent problems such as network downtime that may be caused by incorrectly set management VLANs, you can keep the EAP in the default VLAN 1 and also set ACLs to play a role in preventing guest clients from accessing the management interface.

Additionally, the management VLAN should be Tagged, others should be Untagged.

  @Virgo Thank you, I did not realize it is a normal process to send traffic to the controller as well.  Do you have any documentation on this, so I can better understand and make sure my configuration is correct?  As I said in my previous posts, the clients do not have a stable connection once they go onto the EAP.

  @Tyrade 

Like this:

How to configure Management VLAN

  @Virgo Yes I have setup the management VLAN correctly, and I don't really believe the AP will send traffic to the controller as specified. I think my logs speak for themselves.  Even with a management VLAN set, the controller is not tagging traffic for VLAN 600, it's just not tagging it.

Also, the traffic destination MAC address is the AP client, not the controller.

I honestly think I have hit some bug. I agree it makes no sense I would hit a bug like that for such a common configuration, but I bought this $150 AP to use it and I can't.

Is there an easy way to engage the vendor? 

FYI, still happening after zeroizing controller and AP.

  @Tyrade 

so based on the previous replies, you did follow Virgo's guide and config it based on the correct steps.

then your cisco switch still shows up in the logs like that? yes or no?

next, did you verify this by wireshark?? what does wireshark say about this?