PDOException when saving node with AudioRecorderField Occurs on client's computer but not mine. Does not appear to be a user-related problem. Using SoundCloud recorder.

PDOException: SQLSTATE[22P02]: Invalid text representation: 7 ERROR: invalid 
input syntax for integer: "NULL" LINE 4: WHERE (base.fid IN ('NULL')) ^: 
SELECT base.fid AS fid, base.uid AS uid, base.filename AS filename, base.uri 
AS uri, base.filemime AS filemime, base.filesize AS filesize, base.status AS 
status, base.timestamp AS timestamp FROM {file_managed} base WHERE (base.fid 
IN (:db_condition_placeholder_0)) ; Array ( [:db_condition_placeholder_0] =&gt; 
NULL ) in DrupalDefaultEntityController-&gt;load() (line 196 
of /Users/Shared/Server/HTTP/chinese/includes/entity.inc).
Looks like the problem was with the PHP upload limit. Seemed to be a computer problem because I always used short recording files when testing, while my client tested with a full recording.