Answer to: Why is the device not turning on?Try plugging in your tablet. If the charging light is lit, then let the device charge for about twenty minutes. If it isn't lit, check the Troubleshooting Page for replacing the charge port and other hardware issues that it could be. If the light does stay on and the tablet seems to be charging, try turning the device on while it's still plugged in to a power source. If this works, your battery isn't able to hold a charge and again you may be able to find more help on the troubleshooting page.
Answer to: The camera takes blurry picturesYou have a couple of options here. The first thing I would suggest is to make and sure that the lens itself doesn't have any residue that could be affecting the camera. Next, try turning the device off and on and see if it is fixed, it's possible that the problem was just a glitch. If you are still having problems, try downloading a picture-taking app. There are tons of options and this could be a solution if the problem is in fact a software issue. There are also apps devoted to sharpening blurry images so check those out too. If it still isn't resolved, it's probably a hardware issue, in that case look at the guide that covers camera replacement. Troubleshooting page
Answer to: Buzzing Speaker when playing musicIt sounds like it may be clogged with dust or is becoming disconnected from the motherboard. try this: Pry the back off of the device with your finger tips or a paperclip. The speaker is located at the bottom right corner of the device. In order to remove dust, try blowing on it or using compressed air. If the problem still persists, check and make sure its connected properly to the motherboard. If none of these things work, you may need to invest in a new speaker. Also try the troubleshooting page: Azpen A740 Troubleshooting