In the last few days i noticed a record for sale on ebay usa, (book price £150) which sold for around $80, then a day later noticed another copy by the same seller up for auction. (Described in the same condition, M-)

Having looked at his feedback it shows he's sold at least 6 copies in the last 2 months, a quick look at popsike and another record auction info site shows no mention of any of them.

Would there be a innocent explanation for this?

In the last few days i noticed a record for sale on ebay usa, (book price £150) which sold for around $80, then a day later noticed another copy by the same seller up for auction. (Described in the same condition, M-)

Having looked at his feedback it shows he's sold at least 6 copies in the last 2 months, a quick look at popsike and another record auction info site shows no mention of any of them.

Would there be a innocent explanation for this?

Only that Popsike is selective about what it chooses to list...

Not only do popsike and collectorsfrenzy miss auctions but popsike collects data and bulk uploads it in intervals (once a month?? i can't remember), so you won't see new results right away. collectorsfrenzy is updated daily. Also buy it nows and second chance offers would not be listed on either site, and it's very possible that the seller did that if s/he has quantity. Finally, a seller can ask popsike to take down an auction if s/he wants to but that is an unlikely explanation for this case.

likely that seller has a found an amount and only letting them out one at a time or maybe offering copies to highest bidders to maximise the return he would get

popsike seem to be getting selective about what they show and some titles have been weeded of sales .

possibly because prices are falling as buyers are hard up .its not as buoyant as it was

Not so sure about buyers being hard up, I think many collectors have had enough of ebay and no longer use it. Many use other sites now preferring straight cash deals.