Perhaps you could compress a simple problem project file into a ZIP file and post it here as an attachment so we can have a look at it and see what's (not) happening? In XP, right-click the project file, select Send To ... compressed (Zipped) folder). drag any other media files into the Zipped folder file, when you reply, scroll down a bit, open the "Additional Options" section if needed by clicking the double downwards arrows, click on [Manage Attachments], browse to your ZIP file, select and Upload it.
That's one of my favorite reverbs, and I've never had trouble with it on my ancient "pre-core" 2 ghz Celeron. Which figures, because I'm thinking I'm finally going to be able to upgrade to a dual-core computer soon: "I'm not going to be able to use Kjaerhaus Classic with the new computer...????" Uhg.
--------------------- Я научилась просто, мудро жить,Смотреть на небо и молиться Богу... А. Ахматова
When a plugin gives problems, a good way to know if the problem is related to the host or not, is using it through a wrapper. By example, load Phrazor, or chainer, and then load The Kjaerhus Reverb inside of it. Look if you have the issues with the CPU and the sound, and report back. luck!
A simple test can be done by opening an empty project and adding a track with the offending FX in it - nothing else. Then take a look at the CPU usage.
--------------------- They may forget what you said, but they will never forget how you made them feel.
Exactly. KJ classic reverb is a light weight verb and should cause no such problems. Sounds like something is screwy within your computer, not reaper or the plug itself. Crackels and such points to buffer settings and if you need extra buffering for CLASSIC, there's something not good going on with your computer. You could even have a look at all the anticipative preference settings in reaper setup and see which ones might help. It could just be a setting that's configured to work against you, at the moment. There's a LOT of preference settings in reaper, which is a good thing- and at the same time an annoying thing. Just more fiddling to go through at times. But for a plug like classic?! Seems strange to me. Frankly, I have a love/hate relationship with computers and software daws. I hate all the bullshit it opens up, but I love all the options it opens up. Annoying as all hell, but worthy. Good luck with that plugin. Dan