Are you using the p2pp option for you palette? If so, in the palette plugin on the octo, there is a setting to adjust printer speed when splicing. If you have a lot of short splices, you can cause a buffer crash.
Are you using the long tube by chance? I had the same problem - the solution was to make a custom tube length that is shorter to solve the issue. It’s been reported it’s a known issue on the long tube in the firmware.