What do you mean "clips out"? Please give more information.

[EDIT]

I know what you mean now (I'm pretty sure at least), all you should have to do is tweak your sound card preferences (Edit>Preferences>Audio), i.e. change the soundcard to the right setting, or use ASIO4all if you have a not-so-good sound card.

Also, increase the buffer sample rate to the minumum amount you can without any clipping. My sound card is a Creative Sound Blaster X-Fi, and I have the buffer set to 512 samples with somewhere within the region of 15-32ms of delay.

The higher you set the sample buffer rate, the slower Reason's reactions to your keyboard is, therefore you get a delay. It's not worth dragging the buffer up more than you need because there is no noticable difference.

Hope this helps
TTC.

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