diff --git a/lib/galaxy/visualization/tracks/data_providers.py b/lib/galaxy/visualization/tracks/data_providers.py
index d1ce03433b0..79c5908a0ad 100644
--- a/lib/galaxy/visualization/tracks/data_providers.py
+++ b/lib/galaxy/visualization/tracks/data_providers.py
@@ -718,7 +718,7 @@ class BamDataProvider( TracksDataProvider, FilterableMixin ):
             else:
                 results.append( [ "%i_%s" % ( read.pos, qname ), 
                                 read.pos, read.pos + read_len, qname, 
-                                read.cigar, strand, read.seq, [read.mapq, 125] ] )
+                                read.cigar, strand, read.seq, read.mapq ] )
                 
         # Take care of reads whose mates are out of range.
         # TODO: count paired reads when adhering to max_vals?
diff --git a/static/scripts/trackster.js b/static/scripts/trackster.js
index 9e1a098d91c..2013ae006ae 100644
--- a/static/scripts/trackster.js
+++ b/static/scripts/trackster.js
@@ -2480,14 +2480,27 @@ extend(NumberFilter.prototype, {
             return updated;
         }
         
+        //
         // Update filter's min, max based on element values.
-        if (element[this.index] < this.min) {
-            this.min = Math.floor(element[this.index]);
-            updated = true;
+        //
+        
+        // Make value(s) into an Array.
+        var values = element[this.index];
+        if (!(values instanceof Array)) {
+            values = [values];
         }
-        if (element[this.index] > this.max) {
-            this.max = Math.ceil(element[this.index]);
-            updated = true;
+        
+        // Loop through values and update min, max.
+        for (var i = 0; i < values.length; i++) {
+            var value = values[i];
+            if (value < this.min) {
+                this.min = Math.floor(value);
+                updated = true;
+            }
+            if (value > this.max) {
+                this.max = Math.ceil(value);
+                updated = true;
+            }
         }
         return updated;
     },