They're not exactly the same as the problems posted here, but my problems with UAD and Sonar X3 are documented in this thread started back on October 13. http://forum.cakewalk.com/Lovin-X3-But-Not-UAD-m2911112.aspx
 
I have contacted both Cakewalk and UA support about the malfunctions. Both responded that they are aware of the issues, but UA went so far as to say that a number of users are experiencing problems, they consider it a bug and they are working on a solution for an upcoming UAD update.
 
My investment in the UAD system is in complete limbo until a solution is presented. As much as I love some of the UAD plugins, I simply can't use them with my DAW of choice. I enjoy the features of X3 too much to go back to X2 (which has its own problem with the Ocean Way plugin resetting the distance on the "near" mic). Thankfully, X3 is so heavily packed with its own set of plugin's that I can still get work done.
 
Here's hoping that UA and Cakewalk put their heads together and help all of us UAD/Sonar users soon.

Well after trying #2 and #9 yup I suggest you go and talk to their support. You can point them to this thread. Cheers...

I tried again today on a fresh install of Sonar X3d, fresh install of UAD 7.4.0 (not a clean windows install, but fully uninstalled both Sonar/UAD, all drivers, all filesystem files/folders, every reg entry I could find, etc.), tried the trick from the other post about pointing VST plugin scan to x64 versions of UAD only (tried both UAD and Steinberg folder locations for x64), no change in results.  
 
I'll post to UAD support & flag both these threads as well, and hopefully between the two of them, Cakewalk and UAD can sort it out.  Considering everything works perfectly when I go back to X2, it makes me think it's a Cakewalk issue, or something CW changed in X3 that UAD hasn't 'caught up' to yet.  Either way, I'm hoping for a resolution soon.
 
Thanks for listening everybody.

Because of this problem, I am not using X3 for now. UAD problem in FX chain is really big bug. I hope it will be solved in some update.

Since X3 I never put UAD plugs in the pro channel fx chain ,,, But frequently have to reset the Global FX by pass to get them to sync back up  ,,,,,,, and When  UAD plugs just stop working I got to re open the project to get them back.
It sucks !!!!! All my projects  are running about 60 UAD plugins

So, this has not been fixed... There is no way I am going to open up every channel that has a UAD plugin in the FX Chain and then toggle them to make them work. I hope someone is working this! It is extremely irritating and makes the FX Chain unusable. Note, UAD plugins work fine in the normal effects bin, just not in the FX Chain of the Pro Channel, correct?
 
Thanks

Yes, in FX bin plugins are working, but we really need to put them in FX chain...

An alternative:
http://www.store.cakewalk.com/b2cgbp/ProductInfo.aspx?productid=30-BCPW1.00-20E
 

CakeAlexS
An alternative:
http://www.store.cakewalk.com/b2cgbp/ProductInfo.aspx?productid=30-BCPW1.00-20E
 

Alex, can you verify this works with the UAD stuff?  It will be irritating to shell out $50 for this, but I think it might be worth it for a couple of guys I know.
 

Nope I don't have UAD. But here's a demo:
http://www.bluecataudio.com/Products/Product_PatchWork/
 
Cheers...