SRD4900 Sylvania DVD/VCR Combo

Please try a different type of DVD, if the problem persists try a music CD. If the problem goes away then your unit is only reading cds' and NOT DVDs equals defective DVD player

There is hope to recover from semiconductor problems such as condesation or overheating. You have to play cd as long as possible, let the unit cool down. Then try dvd again. If works, keep standby power on, forever, to keep moisture out of your dvd/vcr combo.

you were saying some? and not all the cds and dvds? it may be that those other discs are unreadable anymore caused by scratches, marks, or the like. if other discs can be read then the player is all good. also check what file format you are trying to play. it may also be that the file format you are playing is not compatible with the program you are using to play it with like windows media player, media classic, etc.

One simple solution is to unplug the unit for 30 seconds then plug it back in. Worked like a charm for me.

It is a DVD ROM drive which stands for DVD Read Only Memory. In other words, this drive is meant to only PLAY DVDs and CDs but NOT save data to them.

To burn CDs you need a CD burner. Burners are of 3 types:

CD writer only burns and reads CDs.

Combo drive reads CDs and DVDs but only burns CDs.

Super drive burns and reads from CDs and DVDs.

As you go higher in functionality, the price also increases. Check your needs before you plan to buy one. Also compare prices of all the drives. Note: burn-able media costs are separate.

Press the eject button on the DVD player. When you hear it try to open, tap the player gently but firmly on the top by the tray door. It may take a few tries to get the timing down and just how firm you need to tap it.

Please clean laser lens with good quality cotton bud gently and check dvd disc playback, if still does not play, replace optical lens block.
Let me know model number of your Sony DVD-VCR combo to provide you optical laser block part number info.
Thanks.

You may have a dirty lens on the DVD read head. There are CD/DVD cleaning kits available at some drug stores and electronic stores. Do not get a "CD cleaning kit" (that only cleans the discs), get a "CD/DVD lens cleaning kit" (it will have a special CD and cleaning solution) for $10 to $20.
If that's not it the DVD illumination LED may be dead. If it still plays CDs, but won't play DVDs, that's the problem. There are separate LEDs for playing CDs and DVDs.
Either way, if the cleaning doesn't work, it has to be fixed in an electronics shop.

DVD/CD-RW combo drives are capable of reading the DVD's but cannot burn so try playing a DVD with some content on it also Download VLCPLAYER 
from :http://www.videolan.org/vlc/
if you don't have a DVD player already on your system. As far as CDs are concerned it can both read and write to CDs

There's a problem with the tape drive, so it's shutting down to prevent damage to the tape. Someone familiar with VCR mechanisms would probably have to see it in action to identify what's wrong. Most of them act in a similar fashion, so if you have a working VCR, you can take the cover off and watch it load a tape, run it, rewind and eject, then compare with the non-working unit. The parts won't be interchangeable, but the tape loading will look much the same. You can comment on what happens and I can try to explain what I think is going on. Better yet, if you could post a video of the internal mechanism while it tries to load a tape, that would be very helpful.