Same tips as I posted in this other thread
viewtopic.php?f=21&t=15200#p269919Update the firmware, if it is not on the latest version. The latest is 4.30. Check by going to Settings/System/About
The other things I will add to the other post - to save battery on the eTrex 30:
- Set the backlight to the lowest setting or off if that works for you. The screen display remains on when the eTrex is powered on, even when the backlight is off. I also have my backlight timeout set to the lowest - 15s
- Set the barometer Pressure Trending to Save When Power On (instead of Save always, unless you want to record the barometric movements), or Set the Auto Calibration to Off (but this will mean you need to manually calibrate it if you want a more accurate elevation). These are in the Altimeter setting
- If you are not using any ANT+ sensors, make sure the ANT+ is off, under the Setup/ANT Sensor I think these are off in the default profile, but check to make sure it is not looking for sensors
A DIY case might help as well
viewtopic.php?f=21&t=20683 Also in that thread, I have pictures of my eTrex 30 with a cutout adhesive foam around the joystick to prevent accidental presses. This seems to have been working nicely for around 4 months or so now. It's prevented accidental presses and waypoint deletions when the eTrex is used in a case.

Also saw in the other thread that you have the preloaded microSD card with the topo maps. These maps are locked to the SD card, so don't lose it! The SDcard slot sliding lock can get into the unlocked position when changing batteries, which has happened to me.
And you can also still use andrewp's OSM topo maps if you want. Copy the OSM files to the \Garmin directory of the device (or the SDcard), and in the Map Settings just enable or disable it as desired. It's best to only enable one map at a time.