Karr, can you help us?


I have been trying to get LiteOn support to understand a problem with the 5S and 6S drives not writing -R Lead-In properly. I have not made much progress with them and I’m not sure they understand what I am trying to point out. Simply put the Lead-In area is too wide. This is causing recognition problems with some players and DVD drives. This very same problem has happened in the past with the 411/811 and 451/851 drives. It was eventually fixed with a firmware update. I can provide additional details if needed and have some pictures good Lead-In’s vs. bad Lead-In’s. I would really like to see this fixed otherwise I have 4 5S and 6S series drives that I simply can’t trust to produce proper -R burns.


OK, I’ll help you. And please give me the additional information such as good Lead-In’s vs bad Lead-In’s.
Thank you very much !

Thank you in advance for your help. I have attached two pictures that were posted in another thread that point out the Lead-In problem we are seeing. This happens with all -R media.

First a -R burn from the 1635S drive and then a burn from a 1633S.

Hydrocardiac posted these images in this thread:


As you can see the Lead-In area is considerably wider on the 1635S burn. This will cause problems with some drives and players. Also look at these threads, if you have a chance, as there are other members having these issues. LiteON support asked for MID’s from smartburn so I sent them some but this happens with all -R media I have tested and I have many different MID’s.



There is a physical difference in the above burns. As I told the support person, they must burn a -R and a 3S drive and then do the same burn on a 5S and 6S drive. Then actually look at the Lead-In so they can see the difference. I am sure this can be corrected by a firmware update. I have been using LiteOn burners since the LDW-401 and this problem was present and corrected on some of the early drive’s (422/811/451/851). I hope this information is helpful in understanding the problem.

Hi worker, I’ve got exactly the same problem here with a new 1635S that I just bought. The DVD-R’s that it burns wont always detect properly (so some wont play) in my home player.

Thanks for posting those pic’s, that was exactly what I noiticed when I looked at my burnt DVD-R’s to try and figure out why they wont play. It almost looks like this drive starts burning them in the wrong position, like some 2 mm or so further from the hub compared with discs make with other burners.

I’m sure that this is what’s causing my problems because when I scan these discs some have quality that is quite near perfect (extremely low PI/PIF). Yet they still wont play in my home player, it’s very frustrating. When I put them into the home player it scans them for a comparatively long time and then makes all sorts of horrible seek type noises (noises that it never makes with discs burnt using other burners). It’s seems like the player just cant figure out these discs. Eventually some of them play (say after 20 seconds or so of horrible seek noise) but some just wont play at all.

PI/PIF scores on some of these discs are as low as 0.7 PI average, 4 PI max, 0 PIF average, 1 PIF max and 28 PIF total (that’s a near perfect burn IMHO!) but I’m still having problems playing them. Ouch!

Thanks for all your work on this guys. I just ordered a new Liteon and I am sure I would have been driven crazy on the occasional -R I burn. No way I could have figured this out not having gone through it before.

The original LiteOn DVD burners had the exact same issue, although it’s not really clear whether the issue lies with the players or the burners. Anyway, all the “3” series burners had the same thing with various FW versions.

Hi Karr, thanks for your precious job!
Same problem for me with my 1635S (YS0W). The LeadIn don’t start correctly. The strange thing is that it happens with all the discs that I have tried (TYG02, ProdiscF01, MCC03RG20) unless an old -R 4x (ID INFOSMART01). :confused:
I have contacted LiteOn two times but they have not understood the problem. They have asked me to send them the SmartBurn result of the disc that have the problem. :doh:
Read their answer here (post 73) :a

Would this problem also apply to -R data discs? That could explain why my old Samsung DVD-Rom takes so long to access a Verbatim -R backup disc I burned with my DigitalMax (rebadged 1635s). Like so long that I start thinking I should CTL-ALT-DEL to see what’s stopped responding, but then it finally shows up in Explorer.

Yes, it does not matter if it’s data or video.

All I can say is ditto that.

My reply from LiteOn was as follows:

[Reply from Lite-On]
> Since the discs burnt by SHM-165P6S could be properly read by the
> mentioned two drives, that seems the drive work properly.
(“mentioned two drives” are the drive that burnt the discs and a Plextor 712A, none of the other three dvd (computer) drives in the house can find the lead-in.

As mentioned in another message already linked in this thread,
“They certainly need to train their support staff to do other than
create disgruntled customers who will badmouth the brand whenever
the opportunity arises…”

Thank to all who have been pursuing this strange problem.

Oh yes, the “m” firmware for the SHM-165P6S has not fixed the problem.

I still rely on the trusty Plextor for back-ups.

I view my LiteOn purchase as a ! BIG ! MISTAKE!

If the problem was acknowledged by customer service then I
would feel that all my wasted time and discs at least had some
role in solving a problem

To be told that there is no problem makes me feel like foolish for
wasting my time trying to troubleshoot the problem and for thinking
that customer services would help to resolve the issue.


I’ve just attempted to quantify the amount by which this lead-in thing is in errror by. Making some measurements with a set of plastic vernier calipers I just got the following data.

  1. GSC003 (DVD-R 8x) burnt on LG GSA-4167B
    Diameter of end_of_lead_in circle = 45.5 mm

  2. GSC003 (DVD-R 8x) burnt on Liteon 1635S
    Diameter of end_of_lead_in circle = 48.0 mm

  3. Ricohjpn001 (DVD+R 4x) burnt on Liteon 1635S
    Diameter of end_of_lead_in circle = 46.0 mm

These measurement are only approximate, the calipiers measure easily to 0.1mm but the accuracy with which I can align the edges to the “bands” on the media limits the accuracy to about 0.5 mm.

Note that the +R burnt on the 1635S is very similar to those burnt with other burners. I didn’t measure any +R’s burnt on other burners here but I can tell you that visually they look to be the same. Additionally the +R measured here (burnt with the 1635s) was only 0.5 mm different to the -R that was burnt on my LG drive, and since 0.5 mm is about the limit of these measurments then I’d have to say there is no significant difference there.

But look at the -R burnt on the Liteon 1635s, it’s a 48 mm diameter as compared with only 45.5 mm for an identical media (from same spindle) burnt on my LG. That’s a huge discrepency!

I then made an attempt to quantify just how much data this extra diameter would correspond to. Assuming constant linear data density I worked out the formula that :

data = constant (outer_diameter^2 - inner_diameter^2)

I first estimated the constant from measurements of the inner and outer diameters of a full disc and the known capacity of a full disc. I then used that constant to figure out how much data must be in that extra 2.5mm diameter of the liton burnt -R’s and I got a figure of about 95MB

So just incase the guys at liteon cant figure any of this stuff out for themselves maybe we need to email them and just tell them that they need to make their leadin about 90MB to 100MB smaller.

At diameter of 48 mm main data is started. It’s quite hard to change start position because addressing information contained in pregroove. Lead-in area consist of 53344 sectors, 45664 of which is Initial Zone (all main data set to 00, so it don’t contains any information). Remaining 7680 sectors can contain some information. So, there’s can be incomplete lead-in, without large initial zone.

This is all good stuff. I think we will get some attention on this issue. I hope Karr has had a chance to look all of this information over.

Thanks for the info midi, we need someone here who knows something about the format of the leadin etc. Can you help us understand why these liteon burnt discs look so different in their starting position when compared with discs burnt by other burners. With DVD-R burnt on my LG GSA-4167 the main data appears to start at about 45.5 mm diameter but with the same discs burnt on the liteon 1635s it appears to start at a diameter of 48 mm. If 48mm is the correct diameter for data to start then why do other burners seem (based on the visible zones as seen in the photos posted above) to start at a smaller diameter than this (45.5mm for example).?

“45664 of which is Initial…” OK that’s looking like it might be the difference between these liteon burns and the others. 45664 times 2048 bytes per sector gives 93MB, this is almost precisely the decrepency that I calculated! I think we’ve finnally pinned this down. These liteon model are NOT writing those 45664 sector in the same way that other burners are doing it. What the other burners are doing with those sectors that these liteon drives are not doing I don’t know, but for the burnt media to look so physically different there must be something going on in that “Initial Zone”. I think we are finally starting to get some understanding of whats going on now.

That seems to be what is going on here. As MIDIMaker indicated the start of the data zone is, according to specification, @ 48mm. This is correct as compared to other -R burns from different drives and analisys of the data at specific points in the data zone. I can confirm that the data zone is starting @ 48mm on the LiteOn drives and that is correct. The data zone on my Pioneer 110 is also starting @ 48mm although you have to magnify it to see it. The LeadIn zone is divided into several other smaller zones that are defined to have specific data. It seems that one or more of these smaller zones is not being written properly by the LiteOn drives or in such a way that it confuses some drives. I would suggest to LiteOn to look at how they are handling the following sub-zones within the LeadIn zone:

  1. Reference control zone
  2. Buffer zone 1
  3. Control data zone
  4. Extra border zone

So the effect we are seeing here is not that the LiteON LeadIn is wider than normal it is that the data being written there is not the same as the other drives. Visually a specific zone that contains all 0’s will look differnt than a zone that contains all 1’s.

worker, have you used a specific sector viewer/tool like DVDInfo Pro or ISOBuster to clarify the “lead-in” area you are talking about?
If you consult ECMA specification again all guidelines will be given regarding lead-in sector size and start of data zone.

This post is in no way intended as critic, just a reminder from one facing the same problem on a 411 more than two years back. :wink:

As I recall the whole issue from way-back, It’s not so much that LiteOn is out of spec, but that they are pushing the spec to it’s limits, and some players/drives don’t like it. There’s a range that’s allowed for the lead-in area by spec, but that doesn’t mean that all drives/players adhere to that range. Therein lies the problem with specs, they are voluntary.

With the 411/811 drives, there were equal numbers of players/drives that would read the -R and equal numbers that would not. LiteOn never addressed the issue AFAIK, it just went away in later drives - till now. Good luck getting them to address it now, as they do not do routine testing on players.
One thing that did occur in the 411 scenario, is that certain FW versions did not have the problem. I also noted in the 411 that a few -R media types would work, while others would not. Very strange stuff.