Speed problem with 52327S

My drive is the version with EPROM, and i tried all versions from QS0C to the latest version of firmware, it just behave the same. The CDR I used is Mitsubishi Blue Platinum 52x, also tried Ultra Platinum 52x too. Could anyone help me with this problem…
The recorded CDR is ok, but the drive just reduce writing speed in 27-28mins/34-36x
There’s no buffering problem, since the buffer % indicated by A120 is always 100%

Strictly a media problem, the drive is downshifting due to over-temp of the media. In other words, the media is not good enough for high-speed on this drive.

Oh I see, so anyone uses Mitsubishi media have the same problem?
I got 3 versions of 52x Mit cdr, all got the same problem :confused: