MU4E check messages and play sound reminders regularly

The following configuration is in Init.el:

(setq   Mu4e-get-mail-command "Offlineimap"   ;; or Fetchmail, or ...   mu4e-update-interval);             update every 5 minutes (Add-hook ' Mu4e-index-updated-hook (  defun new-mail-sound ()    (shell-command "Aplay ~/music/open.wav&")))

The previous configuration will let mu4e start and check messages every 300 seconds and rebuild the index.

The latter section of the configuration makes the mu4e index update, using the command Aplay to play a WAV file to remind.

One drawback is that when I send a message, the index is updated, but it doesn't mean that a new message arrives. No other hooks have been found, so when I send an e-mail I hear a reminder that I'm not going to read the email.

MU4E check messages and play sound reminders regularly