[squid-users] MP3 files cut short

Hello Squid-people!

On a network that I'm administering there is a weird ongoing problem.
The basic setup is as follows:

Squid-cache -> Apache webnodes -> NFS Fileserver

Strangly enough on some of the website's embedded mp3 files are often
cut short to a mere 2sec file (while they are minutes long). When
performing a hard refresh, the file usually can be played as normal.
I've tried on several operating systems, using different mp3 files,
browsers, ISP connections and embedding techniques. One time it works
the other time it doesn't, it seems to be totally unpredictable.

This all leads me to think that maybe Squid has something to do with it.
When looking in the cache-spool the mp3-files always seem to have the
right filesize (this is hard to check for certain).
There also is enough diskspace and inodes available on the caching server.

As a test I've instructed squid to prevent the caching of mp3-files all
together by using this refresh_pattern:

refresh_pattern -i \.mp3 0 0% 0

and also a .htaccess on a test-domain with these lines:

<IfModule mod_expires.c>
    ExpiresActive On
    ExpiresDefault "access plus 2 hours"
    ExpiresByType audio/mpeg "access"
    ExpiresByType audio/mp3 "access"
</IfModule>

This did the trick in never swapping out, however the problem did not go
away.
I find it very hard to debug this issue and have no idea where to look next.
Maybe I'm on the wrong track in thicking that Squid is involved.

Does anybody have experienced something similar?
Or maybe has a suggestion as to where to look next?

Thanks in advance,
Fili

==Some version information==
Debian Lenny
Squid3 3.0.STABLE8-3+lenny
Apache 2.2.9-10+lenny4
Received on Wed Sep 16 2009 - 10:04:18 MDT