Hidden difference between first and later MIDI messages?

Hi, This is a very strange Bome MT, SansAmp, MOTU Microlite or even Windows 7 bug. I’m hoping someone can figure it out because I’m out of ideas on even how to diagnose the problem.

I’m running MT V1.72 on my Windows 7, 64-bit PC. My PC is connected via USB to a MOTU Microlite, the output of which goes to a SansAmp PSA 1.1. The MIDI Through of the SansAmp goes to the input of a Lexicon MX300. Both the SansAmp and MX300 are set to receive on all MIDI channels to remove the possibility of a channel assignment error so both should respond identically to Program Change commands. Note that when the MX300 responds, it confirms that my PC has sent a Program Change command since it’s at the very end of the MIDI chain; it also confirms I don’t have a cabling problem.

On the input side, I have a Roland FC-300 foot controlled sending Program Changes commands to MT via the MOTU Microlite, and an M-Audio Keystation generating Note On/Off commands.

When I use MT as a MIDI router, i.e. I have the input of the Microlite connected to the output of the Microlite as “MIDI Routing.png” shows below (set up using menu MIDI/ Routing (MIDI Through)…), everything works fine. Pressing on my FC-300 causes both my SansAmp and MX300 to change programs simultaneously.

My problem is when I use a translator rule to do the same thing, e.g. to intercept a program change message from the FC-300 or a note down from my Keystation and output a program change message. When I do so, the SansAmp responds to the first message (as does my MX300) but subsequent messages are ignored—but only by the SansAmp!!!! The Lexicon responds to all of the messages.

I can demo this with one simple rule for the FC-300. The Message trigger is “C1 pp”, the rules section is empty, and the outgoing message is also “C1 pp”. Using the Log Window, I can verify the translator fires and the output message is generated (see “Log window.png” below). The response of my MX300 also verifies that MT has output the indicated message.

Another interesting observation: every time I shut down MT and restart it, it automatically loads the most recent translator. Without changing any settings, when I generate a program change event using the FC300 or the Keystation,, the SansAmp responds to the first Program Change message but ignores any subsequent ones. The MX300, as usual, responds to every message. This suggests there is something different about the first message.

Overall, the fact that the SansAmp behaves differently than the MX300 suggests that the SansAmp has a problem. I would agree except for the following:
1. It works perfectly when MT is simply acting as a router so there must be a difference in how MT outputs MIDI program change messages (possibly in some hidden bits?) when MT is working as a router and when it’s using its translators.
2. Whenever I shutdown then restart MT, the SansAmp responds to the first Program Change message but not later ones. This suggests that the first message is different from the others.

I’ve tried different wiring setups (e.g. putting the MX300 ahead of the SansAmp in the MIDI chain, disconnecting the MX300 altogether, using different Microlite ports, etc.) but the results are consistently the same: the SansAmp won’t respond to anything other than the first Program Change message that is generated by a translator, but it responds to every Program Change message when MT is in Router mode.

Can anyone suggest how I can diagnose this further? Help!!!

Audios

An update: Problem solved.

I replaced my MOTU Microlite with an M-Audio MIDISport and everything worked fine! I literally just swapped the cables over, changed the port settings in my MT translator (since the Microlite ones were no longer available), pressed my FC-300, and the SansAmp and MX300 changed simultaneously.

Since I've never had trouble with the MOTU before, I deleted the device using Device Manager, verified that I had the latest driver setup .exe (for Win7, 64bit), reinstalled the driver (despite having installed the latest a while ago), changed the cables, reset my MT port settings, and tried it again. As before, the SansAmp would not respond to anything other than the first Program Change message!

So, I've swapped the M-Audio back in and since everything works again, I'm calling it a day.

I conclude the MOTU has a problem. Pity. It's neatly mounted in my 19" rack but my MIDISport doesn't have any brackets.

Audios

Audios wrote:Overall, the fact that the SansAmp behaves differently than the MX300 suggests that the SansAmp has a problem. I would agree except for the following:
1. It works perfectly when MT is simply acting as a router so there must be a difference in how MT outputs MIDI program change messages (possibly in some hidden bits?) when MT is working as a router and when it’s using its translators.
2. Whenever I shutdown then restart MT, the SansAmp responds to the first Program Change message but not later ones. This suggests that the first message is different from the others.

Since Motu is working when MT simply routes midi messages I don't think it has problem.Have you try cutting the ground of the midi cable?Sometimes it helps but you might ruin the cable.First make sure that all machines are connected to the same electricity plug.