Is X1D a cumulative update

If I'm not mistaken John, you can install c next and then d. But I have Sonar producer, so it may be different. That's how I did mine here and it worked perfectly.

When you go to the download updates part of the Sonar site, if you read the info for each update, it will tell you what patch can be installed over what version. For example, you may see something like "this patch will work over Sonar X1 , X1 a" where the d patch may say "must have Sonar X1 c installed". Each update/bug fix will tell you what you need to update. Good luck.

-Danny