[e-nsp] Alpine, Multicast and FE-card strange problem

[F J]

Hi,
I have an Alpine with both GE (fiber), GE (cu) and FE interface cards. On 
one of these GE (fiber) cards I recieve lots of multicast traffic (more than 
100Mb/s) from different Mcast-sources. The VLAN is then spread to both FE 
ports ans a GE (cu) port where I have connected a switch.

When I connect a PC direct to a FE port I can only pick up one Mcast group. 
If I connect another PC to another FE port I can also pick up only one Mcast 
group. If I try to pick up another group on the same PC or put the two PCs 
on the same FE port (using a hub/switch) I can only pick up one mcastgroup 
at a time.

I have also connected a switch on my GB (cu) interface and if I then (on 
that switch) connects the same computer to different FE ports I can pick up 
several Mcast groups on each PC.

Therefore I know for sure that the Mcast traffic is perectly fine.

I am of course running IGMP snooping on my Alpine (on that particular VLAN) 
and if I run 'show port util' there seem to be the rigth amount of traffic 
on my FE ports connecting my two test-PCs (that is about 6Mb/s for one 
channel). With two channel I do not get 12Mb/s though, and my picture looks 
bad.

Have anyone seen anything similar with Alpines and FE cards?

Any suggestions what to look for?

Any ideas is of interest...

Best Regards
/// Fredrik