Clonky Gears

mike86 Posts: 34
edited October 2010 in MTB beginners
Hi, im new to this forum and have only been riding for around 6 months.
Im riding a Specialized Hardrock disc, ive been out today to enjoy the rain and the mud, so much fun, i felt like i was 12 again lol.
anyways i noticed the gears would keep slipping and were rather clonky, also the chain would come of and get wedge between the front gears and the frame...
is this due to the amount of mud on the bike or is there a problem, either way how can i stop this?
any help would be great