Why are there so many PS Audio BHK monos and stereo amps for sale so soon?


I've noticed there are quite a number of BHK monos and 250 stereo amps on sale here and on Ebay recently.
Is there something wrong with them?
The  250 I heard at a dealer sounded very good - so are they selling due to reliability issues or SQ issues?
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A quick look see shows dealer ads for new PS amps...not used.
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I just finished looking and can't find a single one on the used market. I would love to get my hands on a used BHK, maybe closer to my price range.
I own one and love it.  While I have not been on eBay much lately I have not seen a single used one for sale here.  It's possible I missed it, but as aolmrd1241 says, all the listings I've seen are for new units.  I did see a pair of used monos for sale on the PS Audio site, but they were in Australia!
Yes, There was a Stereo 250 and there is now a 300 Mono set for sale down under. I didn't realise that the sets on Audiogon were brand new.

I did read in passing on the PS audio forum that there were some issues with transformer hum, I wonder if it has affected the 230V units.