Duplicated IDs

Hi,

I am having regurlarly duplicated rows with the same primary key.

=> select id, created_at, updated_at from tracks where created_at =
'2014-07-03 15:09:16.336488';
id | created_at | updated_at
--------+----------------------------+----------------------------
331804 | 2014-07-03 15:09:16.336488 | 2014-07-03 15:37:55.253729
331804 | 2014-07-03 15:09:16.336488 | 2014-07-03 15:37:55.253801

=> select id from tracks where id = 331804;
id
----
(0 rows)

=> delete from tracks where created_at = '2014-07-03 15:09:16.336488' and
updated_at = '2014-07-03 15:37:55.253801';
ERROR: update or delete on table "tracks" violates foreign key constraint
"fk_sources_on_track_id" on table "sources"
DETAIL: Key (id)=(331804) is still referenced from table "sources".

All colums are identical except the updated_at.

PostgreSQL version is 9.3 and fsync is true.

Any idea how I can clean my table? And then how I can stop this?

Cheers,
Alexis