MLD Service Bulletin 01, 17 March 2004.
This problem can occur with all MLD units shipped before 13 March 2004. The seriousness of the problem varies with the manufacturer of one of the chips inside the MLD/T, so on many units the waveform is acceptable.
The MLD had been shipping for twelve years before the problem was identified in our test workshop. It had also been reported once, but the problem was not properly diagnosed at that time.
The problem affects only the signal at the THRU ouput socket (on the MLD/T), the LINE and MLD/R OUT signals are fine. The defect is that one-to-zero transitions in the serial data waveform are slightly delayed. Most receiving devices have no problem with the slightly-damaged signal. Sensitive receiving devices may report MIDI input errors, or MIDI data may be corrupted.
Please accept our apologies for any inconvenience caused by this problem.
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