Faxing - inbound oddity

I’m new to FreePBX and was able to setup faxing just fine, however something odd is happening with inbound faxing. Some faxes are being received but are not being emailed. I looked at the CDR records and notice the faxes that aren’t being delivered are those marked with “ReceiveFAX” in the App column. Those that do get delivered are marked with “Hangup”. Using PBX Firmware: 5.211.65-12 PBX Service Pack: 1.0.0.0