I found out my JVC dvd player (two years olds) is not supporting DVD+R DL, only + & - single layer. But my burner is NEC ND3500A.
LOL (sorry). My DVD player supports next to nothing, only DVD-R (questionable) and audio formats, CDR (Taiyo Yuden media only, plays fine but player can't find all the index points) and CDRW (4X media is all I tried but all have worked).
The player, Toshiba SD3109, is really old (6 years) so I shouldn't be surprised but it was top of the line in 1998 and cost $515 USD.
It's not a big deal because modern players that are far more capable than mine and I could replace it for less $60-100.
Will it be able to upgrade firmware to support DVD-R DL in the future? And I still don't know my JVC will play DVD-R DL.
Impossible to answer. DVD-R DL does not yet exist.
If and when it becomes available I would not give you good odds on upgrading your player unless the manufacturer promised that feature for the future.
On the other hand, you never know. It may be possible. I seem to recall that some people were claiming to be able to mod their older NEC 2500A burners to do DL but the success rate was only something like 60% with a couple people killing their burners. Perhaps DVD-R DL will be possible on your ND3500A.
I really am curious about the industry change in notation from "Dual Layer" to "Double Layer". It almost sounds like a euphamistic way of saying, "Hey we have two layer burning but if it doesn't work on your standalone player then you are SOL".
<b>A mind is a terrible thing</b>