OK I've just added an old (2-3years) 3com hub to a receiver that I was having problems with upstairs when using several switches in a row (between the music server and the rio there are currently 3 switches and a hub (I'm pretty sure anyway. I've got a gob of wire running through the house)). I took the third switch out and replaced with a 3com hub 10mbps and it seems to work for a change (I've been through 4 songs). How long was it before you started having problems?