Stim Artifact Observed with Digital IO Triggers
I am facing this issue with Digital IO pins for Trigger Insertion with Cyton Board.
It was working fine previously. From December, it has started showing an artifact of 20 to 28 ms in averaged epochs.
I have tried different auditory/visual stimuli and various workarounds of signal processing and trigger insertion. I still see this artifact shown in the image attached.
The same is reflected in generated ERPs.
When I remove triggers from Digital IO pins, I can clearly see noiseless data, but I need the trigger timings to record ERPs with exact timings.
Any kind of help would be appreciated.