You should note that Web MIDI is still a draft specification, and although we've found it to be pretty stable, there could be combinations of hardware and software which have problems.
If you still have problems using MIDI from this site, here are some things you can try:
- Check that you are using one of the browsers listed above. Make sure that the version you're using is at least the version shown.
- Check that you have given permission for the My Marshall site to use MIDI devices in your browser. You will normally be prompted to do this the first time you use the site, but you can view and change the permissions later from your browser settings.
- On Windows, only one application can use the underlying system MIDI driver at a time. Make sure that you're not running any other software that could be using the MIDI port, such as a Digital Audio Workstation or MIDI Mapper.
- If MIDI initially works, but you then start to have problems, close all of your browser windows, and then check that there is not a hidden instance of the browser running in the background. On Windows, use the Task Manager to do this, and on a Mac you can use Activity Monitor.
- If all else fails, try turning your computer off and back on again! Sometimes when things crash, they can take the MIDI drivers with them, and the only option is to do a reboot.
Hope this helps.