With 25rc1 of the SDK tools I am having a problem when starting the emulators from $PATH
➜ ~ which emulator /home/ligi/bin/android-sdk/tools/emulator ➜ ~ emu
If you're launching the emulator from command-line, try setting the current directory to your android sdk "tools" folder first.
This works for me as a workaround:
pushd ${ANDROID_HOME}/tools emulator -avd ${EMULATOR_NAME} -wipe-data& popd