Have you checked the marriage entry to see if any parishes of residence were given, plus witnesses?
A Rootsweb tree shows the marriage as being in Cambridge St Benedict, whereas another Rootsweb tree shows the same date but at Herringswell, Suffolk. When there's such a divergence I always start to get worried!
Where did the marriage information come from, as Cambridge St Benedicts has been extracted onto the IGI and it doesn't appear, nor is it in Phillimore's Parish registers - Marriages for Cambridge St Benedicts
Dollylee - there are 300 Prick/Pryke entries in Cambs on the IGI, so wherever the marriage took place I don't think it was necessarily a mistranscription.
David
As the online tree has sylyal as part of the email address I suspect it's your Rootsweb tree Sylvia. Why do you say the family moved to Herringswell AFTER William was born, when the tree gives a pretty specific birth date of 11 Aug 1793 in Herringswell?