Just talked to Garmin about the periodic 295 crashes, also reported here by others. The fix I was given had nothing to do with vent holes and did not require that the unit be sent back to them.
The guy said, with the unit unit off, press and hold the Quit and Route buttons and then press the On button. He said that I’d probably lose any user waypoints and routes and that WAAS would be disabled but that that this procedure would fix the problem. A future downloadable upgrade would provide a permanent fix and re-enable WAAS.
Haven’t tried it yet, as I want to see if I can save my routes for restoration.