Some quick troubleshooting for the Meizu MX3, released in September, 2013.
No matter what you try, your Meizu MX3 won't power on.
There is a chance that the only problem with your phone is that the battery is drained. Try simply plugging your phone into your computer or a wall adapter, and allow it to charge. If your phone does not charge, you probably have a dead battery, which must be replaced.
The power button in the Meizu MX3 is a very simple, and rather flimsy, button. If you have done any work on your device, or if it has experienced any rough care, the power button may not be seated properly. Simply open your device and make sure that the power button is connected correctly.
For some reason, your Meizu MX3 won't charge at all.
It may be as simple as a bad cable or wall adapter. Inspect the charge cable and wall adapter for any damage. If the phone charges when connected to a computer rather than the wall adapter, your adapter is broken and needs to be replaced.
Your phone is burning up, and you don't know why.
It is possible that your phone is simply under too much of a load (Software-wise). Try turning your phone off normally, and then powering it back on to see if that fixes the problem.
It may seem a tad obvious, but when your phone is charging, the battery tends to get hotter than normal. Try unplugging the phone before using it and see if that brings its' temperature down a bit.
You want to listen to your favorite songs, but your Meizu MX3 just won't let you.
Real quick, check to make sure that the volume on your phone isn't turned all the way down. This can be found in "Settings" under the options for sound. If this is the case, don't worry... It happens to the best of us.
While we know that you wish it wasn't the case, your favorite pair of headphones may simply be broken. Make sure to check for any damage to the cable and use another device to test them. If they don't work on any device, it might be time to consider a replacement.
The problem could also be with your Meizu MX3 (Rejoice, your headphones are safe). While not typical, the audio jack on your phone may have become damaged as it is one of the few components of your device that is open to the elements. If you are sure that your headphones aren't the problem, you'll need to replace the audio jack on your phone.
You have important calls to make, but your phone just isn't cooperating.
Try taking a look at your phone's status bar. Is there a plane icon up there? If there is, try going into "Settings", under network, and toggling airplane mode. Did that fix it? Don't sweat it, we've all been there.
If you replaced the back cover of your Meizu MX3 with a fancy metal one, chances are that your loss of signal was caused by that (Though not alone; A complete loss of signal from this means your signal probably wasn't that great to begin with). If that's the case, either replace the metal cover with a plastic one, or try making calls from an area with better service.