trouble converting to 24kbps without downsizing sample rate?

hey.  I'm using Peak 7 (r.i.p.) with the Lamelib plugin for creating MP3
files.  I've used this rig for years and for webstreaming audio I compress
to 24 kbps, (min) 22.05 kHz sample rate, 16-bit, mono. Suddenly now I can't
compress to 24 kbps without the file downsizing to 16 kHz sample rate.
Weird! It never did this before & I can't understand why it's happening
now.

I did also try compressing with Audacity and it gave me a error message
saying I had to downsize the sample rate in order to compress at 24kbps,
but -- it also gave me the option of what rate to downsize to (including
22.05 kHz).

Any information about this would be most helpful.

thanks, Richard
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