L3 portchannel single TCP stream performance

Hello colleagues,

Im facing strange issue. There is L3 portchannel(2x1G) in my network(ME-C3750-24TE vs. CISCO7604). I have test device(100mbps NIC) on far end(Behind ME). Single TCP stream BW test is oscilating aroung 50mbps. When i start multiple TCP stream test, everything works fine and i get 92mbps results. End to end delay between those nodes is 10ms. None of the links is saturated during test. Balancing is working allright(half/half).

Config:

ME:

interface Port-channel1

description x

no switchport

ip address x

ip router isis

load-interval 30

mpls label protocol ldp

mpls ip

max-reserved-bandwidth 100

end

C7604:

interface Port-channel2

description x

mtu 1536

ip address x

ip router isis

load-interval 30

mpls ip

mpls label protocol ldp

mpls traffic-eng tunnels

mpls traffic-eng administrative-weight 1020

mls qos trust dscp

hold-queue 4096 in

hold-queue 4096 out

end

Any advices are welcome.