Worst emergency instructions ever

This was on a bus (the kind you hire that comes with a driver and miniature overhead video screens). If you can't tell, it's right underneath the window. And it's apparently important.

When I first saw it, my thought was: boy, what a poorly made sign. In an emergency, where time is of the essence, people are going to stop and try to understand it and waste seconds, possibly even minutes, determining its meaning. 

Well, it's been over a day now and I still haven't firmly decided on how to interpret it. If you believe to know what it means, please please let me know.

Oh yeah, and here's a clue: the window on the other side has a sticker that's a mirror image of this one.

Dear People Who Yell Out Of Car Windows

I can tell you think that whatever you're saying is very clever. However, from outside the car it sounds like you're saying "ah-oo-eh". Seriously, I can't hear any of the consonants. If you're trying to engender confusion, you are successful.

The last three times you have tried to communicate with me, that's all I got: three syllables. I think. It may just be one syllable plus the Doppler effect. I still have no idea what you said even though, in each case, I've thought about it for a long time.

Would you mind just sticking to really loud music?

Thanks.