I have a pure-midi project that plays perfectly through the soft synths, but when I export the project or freeze the synths, some of them have notes cut off - they play "staccato" when the audio is played back, either as external audio files (e.g. WAV, FLAC etc) or internally in the frozen synth tracks. It seems somewhat intermittent sometimes the early notes will be fine early in a session, but the same notes will always render poorly once they start doing so.
I have a mixture of soft synths including LASS from Audiobro, and EastWest's Hollywood diamond orchestras through Play. It is the EastWest libraries through Play that appear to exhibit the problem.
The machine has Core i9 processor with 128GB RAM and the samples are stored on a M.2 NVME SSD drive, so should be no issues with performance. Audio interface is Focusrite Liquid Saffire 56.
Any help appreciated.