Just from what little I've asked about at Barber School, the use of shaving soap is prohibited because bacteria will eventually grow on the puck.
If you use a puck of soap, make sure you aren't letting it sit in a shaving mug after use. The moisture left in there is a great breeding ground for germs.
I keep mine in a separate container from the scuttle, and try to make sure it's rinsed off and relatively dry after use.
But yeah, sounds like your soap got the ick :(