MIDI playback error on Sansa e250: "null waveform"

[kfb]

I tried playing a MIDI file and no sound comes out, just the message "crap...null waveform..." printed out on the display repeatedly.  I followed the instructions at http://www.rockbox.org/twiki/bin/view/Main/PluginMidiPlay to download and copy over the patchset to .rockbox/patchset and verified that the patch files were in the right location.  I did this twice to make sure.  I also tried several different MIDI files.  However, I still get the same error message each time.  Any ideas?

[Chronon]

I'm not familiar with that error message.  Shouldn't it complain about a missing patchset if that's the problem?  Which revision of Rockbox are you running?

Hmm.. I'm sorry that I can't be of much help here.  For what it's worth, I haven't had any problems playing back MIDI files on my Gigabeat. 

[nls]

Could you make one of these files available somewhere or link to one perhaps so we can take a look?

[zajacattack]

Either way, most MIDI files still won't play on the PortalPlayer targets.

[Chronon]

Have you encountered this particular error, zajacattack?

[zajacattack]

No, I always get the "Buffer miss!" message; however, I believe that his error message most likely has to with the fact that the PortalPlayer targets can't buffer at 22,050 KHz.

[kfb]

I'm running r17068-080410.  I've attached an example midi file to this post.

[nls]

Does any midi files work for you? I tested the track you attached but it plays fine on my h320 and in the simulator...

[zajacattack]

Are you sure you unzipped the patchset right? It plays perfect on my e280R.

[kfb]

Well, I download 3 more midi files from a different source and tried them, and I also tried downloading and copying over the patch set one more time.  No luck at all - still the same error every time.

[Chronon]

There's another Sansa user having MIDI troubles here: http://forums.rockbox.org/index.php?topic=16540.0

[bascule]

Again, your sample 'Love' file works OK for me on an e280.

It seems your file structure is correct, you should have folder:
/.rockbox/patchset

containing files:
*.pat (lots of)
*.cfg (two of)

[kfb]

It seems your file structure is correct, you should have folder:
/.rockbox/patchset

containing files:
*.pat (lots of)
*.cfg (two of)

Yup, I have those files and folders in the location described.
Argh is there any way to get in touch with the author of the midi plugin and find out more about what the error message "null waveform" is supposed to mean?

[Chronon]

You might try resetting your settings and see if that helps anything.

[bascule]

Well, I've found the error message in the code (http://svn.rockbox.org/viewvc.cgi/trunk/apps/plugins/midi/synth.c?view=markup), but there's no comments that help me understand what's going on here (seeing as I know nothing about MIDI and very, very little about C).

It would seem that you may just be out of luck, as the error only seems to exhibit itself on your device. You may want to hop onto IRC (linked from sidebar) and ask about it there, as that's where most of the actual coders hang out...