diff --git a/src/js/assayJS.js b/src/js/assayJS.js
index 5c8bebc441754931690024218ba2b7810482144c..0f5cdb5ce5f16ea133802f2997c2c89971cfa5fd 100644
--- a/src/js/assayJS.js
+++ b/src/js/assayJS.js
@@ -1562,7 +1562,7 @@ globalThis.SlaveSort = function() {
 		const slaveIndices = V.slaveIndices;
 		const cmp = _comparator();
 		slaveIDs = slaveIDs || slaves.map(s => s.ID);
-		slaveIDs.sort((IDa, IDb) => cmp(slaveIndices[IDa], slaveIndices[IDb]));
+		slaveIDs.sort((IDa, IDb) => cmp(slaves[slaveIndices[IDa]], slaves[slaveIndices[IDb]]));
 	}
 
 	/** @param {number[]} [slaveIdxs] */