I am having a problem with a small 3750 stack (3 switches, 3750-24PS, 3750G-24TS, & 3750-48PS) and multicast. The multicast client, when connected to the -48PS displays degraded performance and dropped frames. This is not the case when connected to either the -24PS or the -24TS. It is the only client receiving that multicast stream, but there are other multicast streams on the switch. The stream is between 5-7MB/s. It is received on a trunked GigEthernet link on the -24PS and is not QOS marked.
None of the individual port counters show dropped packets.
This leads me to believe the problem is associated with the StackWise ring, which is advertised as being 32Gbit and should be more than capable of handling the traffic.
The switches are running IOS version 12.2(25)SEB4, IP Services image.