big industry leaders? sounds like ua added a workaround while cake updated to the newer api?

Please pay attention to the bold letters.. It's worthy to note Cakewalk does not make UA plugins.
 

lawp
while cake updated to the newer api

 
Nope..
 

Noel Borthwick [Cakewalk]
From our side I have now removed custom UA chaining support from SONAR for the next X3 update

 
And...
 

lawp
sounds like ua added a workaround

 
Nope.
 

Noel Borthwick [Cakewalk]
Their (UA's) response was that this API is no longer actively supported by them at the host level and only used by them internally now. I was also told that they would add a remedy from their end.

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Noel Borthwick [Cakewalk]
 the only reason that you see a difference in behavior is because the UAD driver seems to be testing for a specific SONAR version and masking the error messages - which is why the some UAD warning messages started popping up in X3.

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Hopefully this layout will be easier to read.
Ta

nice formatting!

For the Prochannel FX chain issue, can someone try using UAD version 6.3 in 32 bit sonar?  I have found that this combination works without error - no "-21" error, FX chain error, no problem adding plugins while the audio engine is running.  However, I didn't really test the FX chain thing since I never use it, and I'm back on 7.4 using a different workaround for the time being.  6.3 was the last version before UA added the "(Logic Pro) UAD plug-in chaining reduces latency" feature in 6.3.1.
 
 
As far as sorting out what went wrong between Cakewalk and UA, I think that's a subject for another thread.