Different sampling rate between EEG signal and AUX signal, using LSL from GUI [workaround]
I found an issue that sampling rates between EEG signal and AUX signal which contain external trigger signals turn to be different values when transmitting them via the Lab Stream layer.
I tried a real-time EEG analysis to communicate them using Matlab and LSL, however, the amount of the AUX chunk was a tenth of the EEG signal. (GUI setting below). I used an 8ch Cyton board on this test. As the EEG signal's sampling rate should be 250Hz, the AUX rate goes to be just 25Hz.
The slower sampling rate, especially for ’trigger’ signals coming from the AUX channel, does not allow us to align EEG epochs. An on-set time of an epoch now can be located in between two triggers (since EEG is sampled in 250Hz and Triggers is sampled in 10 times sparse time window). This may cause serious ‘jitter’ problem and we cannot guarantee the same onset time of collected epochs.
This issue occurs in both macOS and Windows 10. Could you find a way to utilize the same sampling frequency 250Hz both for EEG (timeseries) and triggers (AUX)?