error when running pt-query-digest

The instructions in the README say to get data in the db to run:

pt-query-digest --user=anemometer --password=--review h=dev-sqldb1.domain.com,D=slow_query_log,t=global_query_review --history h=dev-sqldb1.domain.com,D=slow_query_log,t=global_query_review_history --no-report --limit=0% --filter=" \$event->{Bytes} = length(\$event->{arg}) and \$event->{hostname}=\"$HOSTNAME\"" /home/user/slow-queries.log

When I run it I get the error below.

Pipeline process 5 (iteration) caused an error: DBD::mysql::st execute failed: Incorrect string value: '\xAC\xED\0\x05s...' for column 'sample' at row 1 [for Statement " INSERT INTO `slow_query_log`.`global_query_review`
(checksum, fingerprint, sample, first_seen, last_seen)
VALUES(CONV(?, 16, 10), ?, ?, COALESCE(?, NOW()), COALESCE(?, NOW()))
ON DUPLICATE KEY UPDATE
first_seen = IF(
first_seen IS NULL,
COALESCE(?, NOW()),
LEAST(first_seen, COALESCE(?, NOW()))),
last_seen = IF(
last_seen IS NULL,
COALESCE(?, NOW()),
GREATEST(last_seen, COALESCE(?, NOW())))