Why don't you run Dosbox natively on OS X? Running emulation inside a virtualization has proven to be problematic (for example mouse movement/precision).
Also play with the midi settings in the dosbox config.

I've tried native OSX Dosbox and also native ScummVM. Both have issues with Lucasarts and Sierra games which use the Midi Message and also Playmid to emulate GM gets stuck.

It seems the usb device is not maybe 100% compatible ?

Could you do a detailed bug report on what is wrong with native dosbox? It's a much better way to get to the root.
But yes, the USB device might just be bad since you seem to have the same issue in native dosbox and in parallels dosbox...

Is it a cheap no-name adapter from eBay?

Can you test it on a Windows PC?

Its this one:

http://www.ebay.co.uk/itm/321479639414?_trksi … K%3AMEBIDX%3AIT except mine looks like it but without "Midi" written on it. But that is the auction the actual sale I bought it from.

3.39 GBP from eBay, so yeah quite cheap.

I tried it on Win 7 through Parallels on the Mac. I don't have any PC's set up, just Macs. Unless, I guess I could try it on an old Pentium III laptop I have which has XP on it. But I doubt DosBox will even run on it.

Of course DOSBox runs on XP 😀

There was somewhere an interesting analysis of those usb adapters. The ghist was that thise can be pretty badly wired inside and not always looking the same.
I have one of those that works perfectly but the post/blog/whatever had a bad apple that needed to be rewired to work.

Hm, so there is something wrong with those crappy cheap adapters.
I made a video about mine a while ago.
https://www.youtube.com/watch?v=hY-y7LovroA

I found they work ok with DOSBox, but not the other way round, as a MIDI input.

Best to buy a decent brand to be honest.

I think the issue with the one I have is actually PROGRAMMING the MT-32. In a sense that games which don't send a Midi Message* appear fine - Dune, Lotus III etc.. but games that do Midi Message* do not work properly and show no Midi Message* - Ski or Die, Monkey Island II, Police Quest II, Wing Commander etc...

Also, Playmid mt2gm just gets stuck. Also if I quit Dosbox during monkey island II/PQ2 etc during certain points the green LED gets stuck and I need to reset the MT-32.

*MIDI MESSAGE = "INSERT BUCKAZOID" etc.. etc..

The MT-32 the same one worked fine using a real PC with real MIDI ports (SB Audigy II Gold with MIDI breakout box)

Found the blog post http://www.arvydas.co.uk/2013/07/cheap-usb-mi … ay-be-required/
Reading the comments is good on this post 😉
Get rid of this cable 😉

The funny part is, those missing components fit quite nicely! You're not paying for a MIDI adapter so much as a cable, plastic casing, and PCB. Supply some of the SMD components yourself.

That isn't, however, what they advertise.

Interesting read. Sounds like a lot of work to modify my adapter if it is indeed the case which it probably is.

Can you recommend me an inexpensive adapter which I can use ? The Roland one looks nice but I don't want to spend the best part of 40 Euros on a USB MIDI adapter.

Interfaces from MOTU and Midiman are as or more expensive than Roland. There may be fully functional no-name units or brand name devices on the used market for less.

Dougal, before you buy yet another (and well may be potentially broken) USB-MIDI cable, I'd recommend to give your cheap cable a try within a Linux VM. Same as you, I also have acquired a cheap one, and expectedly it didn't work with Sysex messages in Windows. But then, I found it working in Ubuntu box just perfectly (I guess cheap OS is tuned to be compatible with cheap devices, heh). So, I ended up with a custom userland MIDI driver that relies on libusb you can find at https://github.com/sergm/munt_devel/tree/mast … windrv/usb-midi. It well may be useful for other cheap USB-MIDI things, I guess.

On the other hand, I've also got a "brand name" USB-MIDI "MIDITECH MIDILINK-mini" cable which costs times more. And it appeared also broken when it comes to transfer MT-32 related Sysexes. So, paying more not necessarily guarantees the cable is suitable.

FYI: I also tried both cables on a Mac lately (just out of curiosity how good are USB-MIDI class drivers in OS X) and both also failed to transfer Sysexes. 🙁

I think those cheap ones were okay at some point but got badly copied later on. As I wrote my cheap one, looking like the one above works fine on OS X, sysexes are transferred etc. But it is about 7-8 years old, so the market might have been swamped by cheap ones since then.

It a process called cost-down. You pull parts out until the device stops working, then add the last few parts back in so that the device still sorta kinda works.

Indeed. But I think it also relates to OS quality coming down these days 🙁

Dominus, I noted my cheap cable looks exactly as one of the recommended cheap cables known to work with MT-32. So, you're seemingly right as usual 😀

Sergm, I'll try your suggestion of Linux. To make things easier for testing I happen to have an old 2006 Intel iMac which as Ubuntu installed on it 😀

In the meantime I stupidly ordered another cheap cable. I also popped down to the electronics shop which happens to be down the road from work and bought a low current opto-coupler and 220ohms resistor just IN-CASE the adapter may need that MOD that Dominus posted.