I finally finished putting my circuits and buttons etc together. I thought I would just have to fine-tune my PD patch for the embedded environment before adding more features, but it's much worse than I expected....

At the moment my PD patch on Bela is a drum machine playing samples, very simple.
The only thing I think is clever is the sequencer: it allows realtime recording with or without quantise, kind of like an MPC. You just set the quantise amount and then drum on the pads. It is a lot more complicated than a steptime sequencer to implement.

I am using Bela's audio outs for audio, a selection of digital ins & analogue ins for button presses, and analogue outs to control an LCD.

The drum machine works perfectly in PD on my Mac.

On Bela I have the following problems:
Playing sounds from the pads sounds great but playing them from the sequencer is glitchy/crackly.
(Bela is at about 44% when the sequencer is not playing and about 46% when it is playing.)
(There is no extra screen activity when the sequencer is running.(

The LCD goes wrong quite often, especially if audio is playing then it goes wrong as soon as it is asked to display something.
(The LCD needs quite precisely timed bursts of info so I am guessing the timing is going wrong.)
(In simple tests the LCD driver I've written seems to work perfectly.)
(I am pretty confident that it shouldn't be possible for characters to "overlap" in time and cause glitches.)

Increasing the buffer size to try and fix the audio problems makes the screen stop working completely.

HELP!