How can I get abstraction-based DSP enable/disable to work reliably?

Systems: Win2K Pd 0.37.1, Hans package. AmdK6/2 350 192Mb RAM, also P1 MMX/233 128Mb

When stopping and starting dsp based on a [metro], this console error message occurs after the 2nd stop/start cycle:

"waveInAddBuffer: Cannot perform this operation while media data is still playing. Reset the device, or wait until the data is finished playing."

The [delay n] time doesn't seem to matter. With [delay 1000] the error occurs the 2nd time dsp is turned on, and each time from then on. With [delay 2000] it occurs at about the 6th time, and so on.

I can stop and start using the "compute audio" checkbox as fast and as frequently as I like; never a problem. Same is true with [; pd dsp $1] messages, when performed manually.

L