If you have a bug to report, it would greatly help if you can fill out this form and follow the initial suggestions to narrow down the source of the problem. If you have a big aversion to filling out forms you can just email me directly but I will probably still ask many of these questions later on :)

1: Remove earlier versions
It is a good idea to get rid of earlier versions of the synth in question to make sure there is no chance of the new version loading outdated dll's.

2: Try Synth in Cantabile Lite with ASIO4all drivers
I always test this situation as one of my main tests and so it is a useful 'common ground' to identify it the problem is to do with sound/hardware or a specific Host. Both of these are not intrusive, Cantabile Lite is a free hosts available from here.

ASIO4all are generic ASIO drivers which work with any soundcard, they do not replace your existing drivers, they just become a new choice in your Hosts driver settings box. You can quicky and safely switch back to your normal drivers after testing. You can get the latest asio4all drivers from here.