Mail shows wrong message body

OS X 10.9.4 / 3.2GHz Quad-Core / 16GB DDR3

Mail 7.3 (1878.6)

IMAP Server at InMotion Hosting

I continue to see messages in my mail folders that have the header information (From / Subject / Date) from one message in the message listings, and the From / Subject / Date of a DIFFERENT message in the message preview.

This is NOT Google. The IMAP server is from InMotion Hosting. On the server, the messages are accurate: the From / Subject / Date information is attached to the message body it represents. It is only in Mail that the information gets scrambled.

I have used the Rebuild for this mailbox, which usually corrects the problem. On occasion, I have to delete the mail account from Mail and add it back in again to force an accurate rebuild.

Why is this happening?

Other search phrases I've used include

Wrong message headers in mail

mac mail wrong messages

wrong imap messages mac mail