Are you sure you have flow ingress enabled for all interfaces? If so and you are still seeing this, you may need to open a support case.
Also, make sure you are using v9 because that tends to be more reliable in general. There could be a bug in the IOS as well, but that is just a guess and not based on any actual Cisco bug IDs.
What do you mean by flow ingress enabled for all interfaces? Is there a configuration I could try?
I enabled CEF as well but no change.
EDIT: I solved the problem. I changed #mls flow ip full to #mls flow ip interface-full and now it is getting accurate results.
Are you using a supported PFC?
When configuring NetFlow, follow these guidelines and restrictions:
I deleted your second post b/c it was a duplicate. Did you have difficulty posting and thought you had to do it twice? I'm asking so we can track this.