Replication failing - IMAP_SYNC_CHECKSUM Checksum Failure

[Tod A. Sandman]

I'm using rolling replication with cyrus-imapd-2.5.9.  sync_client died and I am not able to get replication working again.  I've narrowed it down to one mailbox, user.lamemm7, and I've successfully reconstructed the mailbox on both replication partners with various options, such as

reconstruct -r user/lamemm7
reconstruct -r -G user/lamemm7
reconstruct -r -R user/lamemm7
reconstruct -r -V max user/lamemm7

These all seem to run fine, but still sync_client fails:

% sync_client -v -v -l -m user/lamemm7
.............
<1471887110<NO IMAP_SYNC_CHECKSUM Checksum Failure
imap/sync_client[21652]: MAILBOX received NO response: IMAP_SYNC_CHECKSUM Checksum Failure
imap/sync_client[21652]: do_folders(): update failed: user.lamemm7 'Replication inconsistency detected'
Error from do_mailboxes(): bailing out!
imap/sync_client[21652]: Error in do_mailboxes(): bailing out!
>1471887110>EXIT
<1471887110<OK Finished

and the sync_client log shows:

CRC failure on sync for user.lamemm7, trying full update
do_folders(): update failed: user.lamemm7 'Replication inconsistency detected'
Error in do_mailboxes(): bailing out!

Anyone with ideas on what to try next?