[c-nsp] ME3400 QoS Output drops

[ML]

I'm having an issue which I've been scratching my head about.

I have a ME-3400G-12CS with a 5x gig-E Portchannel using Gi0/12 - 16 
classifying and adding CoS markings for downstream devices connected via 
two 4x GigE Portchannels.  I'm seeing output queue drops on both 
downstream portchannels.  The drops are all happening in Queue 3 Weight 
2 which I'm assuming is the default queue since I haven't applied any 
output policy maps.

What is confusing to me is that there really isn't a speed mismatch from 
upstream to downstream.  Frames should be able to be switched out just 
as soon as it comes in.

Any thoughts on how to alleviate this?

-ML