Ebay Synchronization Add On Kills Page Speed

Has anyone else had a problem with the ebay sync add on killing the page speed of the front end?

As soon as I activate it the pages take forever to load. I had it active for a while before realising and it really affected my sales.

Very keen to get it working but don't want to take the hit on page speed as it makes the website unusable.

Any advice welcome.

Many thanks