Nipype FEAT node crashes when run in parallel

Whenever I run multiple FEAT nodes in parallel, I get the crash below. Running them individually does not result in this crash. Any idea what this crash is caused by?

feat /project/3013068.04/1st_level_test/all_runs/1st_level/_run_sub-002.Training-1.4...project..3013068.04..converted..StressNF../l1_model/run0.fsf
Standard output:
To view the FEAT progress and final report, point your web browser at /project/3013068.04/1st_level_test/all_runs/1st_level/_run_sub-002.Training-1.4...project..3013068.04..converted..StressNF../feat_fit/run0.feat/report_log.html
Standard error:
child process exited abnormally
    while executing
"fsl:exec "${FSLDIR}/bin/feat ${fsfroot}.fsf -D $FD -I $session -stats" -b $howlong -h $prestatsID -N feat3_film -l logs "
    (procedure "firstLevelMaster" line 190)
    invoked from within
"firstLevelMaster $session"
    invoked from within
"if { $done_something == 0 } {

    if { ! $fmri(inmelodic) } {
       if { $fmri(level) == 1 } {
          for { set session 1 } { $session <= $fmri(mult..."
    (file "/opt/fsl/6.0.1/bin/feat" line 390)
Return code: 1

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