Uploading the audio to your server and testing if it works, is really just to try and narrow down the source of the problem.
Since that also doesn't work, it means the problem is likely related to the filter. I seem to recall having a conversation with you earlier about the way you were linking to audio files. What happens if you temporarily disable all filters, and leave only the PoodLL filter enabled? If not, does having only the multi media plugins filter enabled work?
If you get it working that way, then re enable the other filters one by one and see where the problem is coming from.
If it is just mobile devices, I suppose it is possible that the PoodLL filter is not recognizing your devices as mobile. But in that case the multi media plugins filter will probably work.