Beta map from one source is empty multivariate analysis

Hello,

I am using Conn Toolbox to run a multivariate seed-based analysis, while controlling for two other seeds (so I enter three seeds in total). The beta map for source 1 (my seed of interest) looks good, as does the Source 3 Beta map. However, the file of Source 2 is completely empty. I am wondering how this can happen, am I entering something wrong?  

I am using the batch script, and enter the following lines:
batch.Analysis.type=2;
batch.Analysis.sources=batch.Setup.rois.names;
batch.Analysis.measure=4;

where batch.Setup.rois.names is a cell array of the names of my seeds (the 3 seeds).

I am interested in the unique correlation Seed1, while controlling for the other two seeds, so therefore I decided to use the multivariate option. However I would expect a Beta map output for every source.

Thank you.