Offline Credit Card Processing Plug-in Not Sending Emails with Last 4

[artechulate]

I've been using the Offline Credit Card Processing payment method plug-in for a while with no problems but now it is not sending emails for each order.  It is very random.  It will skip sending an email every few orders for a day or so, then work as it should, then back to skipping every few orders.  Since the last 4 of the credit card number is only sent via email rather than stored this is quite a problem.

I am using version 1. 1 on a Joomla 2.5.19 site with Virtumart 2.0.26d.   Other plug-ins that send emails do so without problems.  There have been no updates to Joomla or Virtuemart since the plug-in was installed.

The emails do not bounce. They are not in spam. It's like they are just not generated.

Any ideas how to fix this? Or even where to start?

[jenkinhill]

Support for that plugin is by ticket at: http://extensions.virtuemart.net/support-updates