Problems with CDR-audio blanks?

I own two Marantz DR-700 CDR audio recorders. I've started to have a problem with both machines ( which makes me doubt it's the machines) - the initial stage of recording a one time use CD audio blank involves the machines scanning the disc's looking for errors and to make sure the disc's are registered as "audio" recordable CD's - this process is called OPC - what's happening is that entire batches of CDR-audio blankks are failing the OPC - they can't be recorded on.
I have used hundrerds of Memorex blanks - these quit working in my machines , just tried 5 Imations - no luck - went thru two 50 pack spindles of Maxell's - no luck , TDK's work fine ???? To clarify - once recorded - even older recorded disc's PLAY fine - it's recent purchases that don't seem to be recordable.
Anyone else expereinced this problem? The answer is ???
The answer PROBABLY is: your Marantz recorders need service (maybe you can get a group rate :-) ) Same thing happened to my TASCAM CD-RW700, right after thw warranty expired.
I have a Marantz (Superscope) CDR-630. It will only work with the Maxell Music 80 discs that have the bluish-green color on the business side. I have tried several others, including the new black discs, but none have worked. According to Superscope, the Fuji Yellow discs will work also, but I have never been able to find any of these. All of the Marantz machines were built by Superscope, which is located in Chicago. Hope that this helps.
The problem is that even the Marantz professional machines can not record on data grade CDR discs that are rated @ 40x's or greater. If you can find some NOS 24X's you should be fine but anything greater will not work. My quess is that befor you were using 24X's and now you are using 40x's.
HHB's manage the higher speed discs better.

I own a CDR630 and have accepted that cheap data grade CDR's are not an option anymore, due to the fact that all of them are now rated at 40X's or greater. Now I use Music grade CDR's and pay a bit more.

Also, when buying CDR's look for the ones that are made in Japan. The quality is better for a number of reason that have been discussed here in the past.
Appreciate the help with this problem. Have tried a couple of things - one which seems to work flawlessly - "Fujifilm CD-R All Purpose" blanks work flawlessly. Available from Office Max.
Talked to a tech at Marantz today - he said that DR-700 were designed for 74 min. blanks and will probably have problems with 80 min. blanks. Frankly both the Fuji's and TDK's that I have tried and which work are 80 min. blanks - so I'm not sure he's right about this. I am going to see if I can find any old stock 74 min. CDR-audio blanks floating around to test his idea.
What Marantz told you is what they have been saying for years, albeit, it has nothing to do with the problem. The all purpose disk are audio disk, which as I stated above the Marantz will read. You can use 40X audio disk but you will not be able to use 40X or above data grade. You will not be able to find many 74 minute disks nor will you be able to find many NOS less than 40x data grade disks.

As I have already informed you in my prior response, you will have to accept that you must now use audio grade disks and pay more.

There is nothing wrong with your machine. What you are experiencing is inherent in Marantz machines.