diff --git a/algo/unpack/CommonUnpacker.h b/algo/unpack/CommonUnpacker.h
index 76f182dc653da3dd9b01432a2216d6c434d81279..1834c47729a21b450870ad89c35114a44d854382 100644
--- a/algo/unpack/CommonUnpacker.h
+++ b/algo/unpack/CommonUnpacker.h
@@ -105,6 +105,7 @@ namespace cbm::algo
 
       std::vector<std::vector<Digi>> msDigis(numMs);  // unpacked digis per microslice
       monitorOut.msMonitor.resize(numMs);             // monitoring data per microslice
+      auxOut.msAux.resize(numMs);                     // auxiliary data per microslice
 
       xpu::t_add_bytes(msData.monitor.sizeBytesIn);