pt-table-checksum false positives?

The issue I am running into is that in the first command (using --replicate to compute the actual checksums), I see 1’s appear in the DIFFS column for various tables. However, when I run --replicate-check-only command after the checksum command, it reports no DIFFS. This seems contradictory. I then checked percona.checksums table in the database for some of the tables in question and the CRC is identical on master and slave. In addition, there are no row mismatches between master and slave. Therefore, I’m left to wonder, why did the checksum output report a 1 in the DIFF column?

Has anyone else run into this or know of why this would occur?

I have the same problem using MD5. Same version of PT with Percona MySQL 5.6.

Please use the latest version of the tool. If you have the problem again, please paste the full command, command output and related data from slave server’s percona.checksums table.

It’s been a while but recently false positives have come back:
My versions are:
Server version: 5.6.17-66.0-log Percona Server (GPL), Release 66.0, Revision 608
and
percona-toolkit-2.2.12-1.noarch

my command is the following:
pt-table-checksum --config /etc/percona_tools/etc/ivy-checksums.conf

attached two files:
ivy-checksums.conf
and my and checksums table.

ivy-checksums.conf zipped…

config.zip (622 Bytes)

https://dl.dropboxusercontent.com/u/8584526/files.zip database + config file