gpg: checking created signature failed: Bad signature

[green at mm.st]

The plot thickens.

I have just generated a new keypair on the Arch Linux box where I'm
having the problem and I can use this new key (repeatedly) to "gpg2
--clearsign doc" and it works every time.

So, it seems that the 'Bad signature' issue is related solely to my
'primary' key, which would suggest that hardware is not to blame?

As another test, I have also deleted the primary keypair, exported it
from the (working) Windows machine and re-imported it on the Linux
machine but I still get the intermittent 'Bad signature' error.

Any additional thoughts?