Hello PrsaLab,
The issue you're seeing is caused by Bpod's event allocation scheme. Some modules (e.g. Analog Input) request a minimum number of behavior events on startup, greater than the default allocation of 15. If any module channels are not connected, their events are re-allocated to the modules that need them. If all channels are connected, there are no free events to re-allocate. The develop branch currently has a minor improvement that treats valve driver modules as empty channels, since they are not capable of generating events, but of course that will not help with the present situation.
Commenting lines 124-152 will retain the default allocation of 15 events per module. In your case, retaining the default allocation would specifically result in incorrect assignment of events generated by the second threshold on analog input channel 8 (event #16). If you are not using input channel 8, or acquire with it but do not set its thresholds, you shouldn't experience an issue.
If you need input channel 8, you can mod the r1-configured state machine firmware to add more events. On line 243, set:
const byte maxSerialEvents = 60;
to:
const byte maxSerialEvents = 68;
Then load the modded firmware with Arduino, using the guide here:
https://sanworks.github.io/Bpod_Wiki/install-and-update/firmware-update/#manual
This issue is on our dev stack, and will be fixed in a future update. The update may add a firmware feature to create a pool of unassigned events beyond the default allocation, a user function to manually configure the distribution of events, or both.
-Josh
