Question on slow cooker meals?

I have a slow cooker and I have used it to make mince dishes such as bolognaise etc while I am at work and things like that generally work out fine but if I do say chicken in sauce the chicken turns out really dry and horrible even though theres lots of liquid in there. I cook on 'low' and am generally out of the house for about 9 or 10 hours - I keep reading about people who come home to tasty meals when mine mostly just turn out dry - help! Is it my slow cooker - I've got one of those rival crock-pots with the removable dish which works on stove tops and in ovens - its made out of stoneware - do other slow cookers have ceramic dishes?