MP3's sent as attachments now skipping

[#1]

Does anyone have any idea as to why MP3 music tracks sent as attachments are now becoming corrupted?

I've sent a few different recipients different MP3 tracks (all fine before sending) and when received by the recipients they've been skipping/glitching horrendously. I've asked for them to be returned to ensure that the problem is happening during transmission, and the tracks are definitely corrupted. Never had this problem before.

[#2]

Are you sending directly attached attachments?

No intermediate 3rd parties?

[#3]

Thanks for your reply.

The MP3's are attached to the message directly (Thunderbird email client) and sent directly to the recipient, albeit the Thunderbird email client uses Imap settings to communicate with the Plusnet mail server.

This method has worked fine for the last 5+ years, however recipients are now receiving corrupted files (MP3 tracks skip repeatedly every few seconds) although the MP3's are perfectly fine at the point of sending,

[#4]

Have you tried sending one from another client or Webmail to yourself to see if Thunderbird is corrupting it your end. Or getting the recipient to collect the email in a different client?

[#5]

How about sending a big image file?

[#6]

@stevemccl - When an email attachment is sent it is broken down in to (IMSMC) 64K blocks of base64 encoded data. So from what you are saying I suspect that either Thunderbird or the recipients client isn’t putting the attachment back together correctly.

To test your email client send an MP3 file to your friend and either BCC or CC yourself into the email. Save the attachment and then play it see what results you get.