The FAA in October 2019 issued a special airworthiness information bulletin for the Avidyne SkyTrax 600 series traffic advisory system flight software. Certain versions of the software are causing traffic to display incorrectly on interfaced display systems.

The display issue may result in failure to show some or all of the traffic when interfaced to a display using RS-232, which may be accompanied by an error message. Pilots should watch for sudden disappearance of traffic on the display as this is a sign that the display information is incomplete. The issue will self-correct, but timing of the correction is unpredictable. At this time, the FAA has determined that the issue does not create an unsafe condition that warrants an airworthiness directive.

Affected systems will have part number 700-00185 with software part number 510-00296-000 Revision 00, 01, and 02. Software version Revision 03 does not have the display issue.

Read the SAIB here.