Reads NO DISC Philips HTS3400 Home system

problem with your lens .clean the lens using a lens cleaner disk

the laser is weak. need to replace. you could also try opening unit and clean lens with alcohol.

first clean the laser lens if this donçt solve the problem change the motor disc spindle because are on bad conditions

Your problem is that you bought a Phillips instead of a Sony.  Quality vs. Quantity my friend.
Anyways, your DVD player is set up to play region 1 and the disc you inserting is probably some other region.  Look on the back of the DVD case and it will say what region you can play the disc on.  Also, clean off all the smudge marks on the disc with some glass cleaner and this disc won't play if you got a lot of scratches on the thing.
If the above didn't help, then your fuc..d, cause your laser pickup is dirty or defective.  Run a DVD laser cleaning kit through it, which is available at all the big box stores.  See if that helps out any.  If not, then your truly fuc..d and you need to call the manufacturer if this thing is still under the 1 year warranty.  If your under 30 days, then just take it back to the store and exchange the thing out.

open up the unit and replace the broken drive belt for the dvd tray. us an O ring that you can get at any auto parts store. i replaced mine and it works fine now.

it might be the programs your using to burn your dvds try using windows dvd maker if you have the operating system vista or convert x to dvd if you have xp that should work

almost 50% chance is to for the failure of the lens strip, try to replace with a new one very low costly it arround 4Rs , after rhat this problem presist replace the lens also 

Disc is either to scratched or may have a hairline crack on disc. If this happens to all of your disc's, then you have a laser read problem. This can be caused by high humidity as well as dust and debri. Try blowing the unit out with canned air.

Run a dvd cleaner through system, and try again. If that fails, unplug the HTS from the wall outlet for 10-15 seconds, and replug it. If that fails, it will need to be repaired.

-Tha Mp3 Doctor

If you have a screwdriver q tip and rubbing alcohol you can fix it. Take the screws out remove the cover and locate the laser. It looks like a small lens. Dip the q tip into the rubbing alcohol just get it damp not dripping. Clean the lens with the Q tip and then put it back together.