diff --git a/admin/app/admin/music_session_history.rb b/admin/app/admin/music_session_history.rb
index da621b1aa..37a3d5c16 100644
--- a/admin/app/admin/music_session_history.rb
+++ b/admin/app/admin/music_session_history.rb
@@ -25,7 +25,6 @@ ActiveAdmin.register JamRuby::MusicSessionHistory, :as => 'Music Session History
               row :creator do |msh| auto_link(msh.user, msh.user.try(:email)) end
               row :band do |msh| auto_link(msh.band, msh.band.try(:name)) end
               row :genres
-              row :perf_data do |msg|  link_to('Data Link', "http://#{msh.perf_uri}") end
             end 
           end
         end
@@ -36,6 +35,9 @@ ActiveAdmin.register JamRuby::MusicSessionHistory, :as => 'Music Session History
               column :joined do |msuh| msuh.created_at.strftime('%b %d %Y, %H:%M') end
               column :duration do |msuh| "#{msuh.duration_minutes} minutes" end
               column :active do |msuh| msuh.session_removed_at.nil? end
+              column :perf_data do |msuh| 
+                link_to('Data Link', uu) unless (uu = msuh.perf_uri).blank?
+              end
             end
           end
         end
diff --git a/ruby/lib/jam_ruby/models/music_session_history.rb b/ruby/lib/jam_ruby/models/music_session_history.rb
index fe8e7d082..4d36302dd 100644
--- a/ruby/lib/jam_ruby/models/music_session_history.rb
+++ b/ruby/lib/jam_ruby/models/music_session_history.rb
@@ -5,22 +5,17 @@ module JamRuby
 
     self.primary_key = 'id'
 
-    # for some reason the association is not working, i suspect has to do with the foreign key
     def music_session_user_histories
+      # NOTE: for some reason the association is not working, i suspect has to do with the foreign key (jkolyer)
+      # has_many(:music_session_user_histories, 
+      #          :class_name => "JamRuby::MusicSessionUserHistory", 
+      #          :foreign_key => :music_session_id,
+      #          :order => 'created_at DESC',
+      #          :inverse_of => :music_session_history)
       @msuh ||= JamRuby::MusicSessionUserHistory
         .where(:music_session_id => self.music_session_id)
         .order('created_at DESC')
     end
-    # has_many(:music_session_user_histories, 
-    #          :class_name => "JamRuby::MusicSessionUserHistory", 
-    #          :foreign_key => :music_session_id,
-    #          :order => 'created_at DESC',
-    #          :inverse_of => :music_session_history)
-
-    has_one(:perf_data, 
-            :class_name => "JamRuby::MusicSessionPerfData", 
-            :foreign_key => "music_session_id", 
-            :inverse_of => :music_session)
 
     belongs_to(:user, 
                :class_name => 'JamRuby::User', 
@@ -98,10 +93,5 @@ module JamRuby
       end_time = self.session_removed_at || Time.now
       (end_time - self.created_at) / 60.0
     end
-
-    def perf_uri
-      self.perf_data.try(:uri)
-    end
-    
   end
 end
diff --git a/ruby/lib/jam_ruby/models/music_session_perf_data.rb b/ruby/lib/jam_ruby/models/music_session_perf_data.rb
index 1133cb28e..b23b8daec 100644
--- a/ruby/lib/jam_ruby/models/music_session_perf_data.rb
+++ b/ruby/lib/jam_ruby/models/music_session_perf_data.rb
@@ -7,9 +7,9 @@ module JamRuby
 
     attr_accessible :uri
 
-    belongs_to(:music_session, 
+    belongs_to(:music_session_user_history, 
                :class_name => "JamRuby::MusicSessionHistory", 
-               :foreign_key => :music_session_id, 
+               :foreign_key => :client_id, 
                :inverse_of => :perf_data)
 
     # mount_uploader :uri, PerfDataUploader
diff --git a/ruby/lib/jam_ruby/models/music_session_user_history.rb b/ruby/lib/jam_ruby/models/music_session_user_history.rb
index f4de39dc1..a548f4987 100644
--- a/ruby/lib/jam_ruby/models/music_session_user_history.rb
+++ b/ruby/lib/jam_ruby/models/music_session_user_history.rb
@@ -10,17 +10,22 @@ module JamRuby
                :foreign_key => "user_id", 
                :inverse_of => :music_session_user_histories)
 
-    # for some reason the association is not working, i suspect has to do with the foreign key
+    has_one(:perf_data, 
+            :class_name => "JamRuby::MusicSessionPerfData", 
+            :foreign_key => "client_id",
+            :inverse_of => :music_session_user_history)
+
     def music_session_history
+      # NOTE:  for some reason the association is not working, i suspect has to do with the foreign key (jkolyer)
+      # belongs_to(:music_session_history, 
+      #            :class_name => "JamRuby::MusicSessionHistory", 
+      #            :foreign_key => :music_session_id, 
+      #            :inverse_of => :music_session_user_histories)
       @msh ||= JamRuby::MusicSessionHistory
         .where(:music_session_id => self.music_session_id)
         .limit(1)
         .first
     end
-    # belongs_to(:music_session_history, 
-    #            :class_name => "JamRuby::MusicSessionHistory", 
-    #            :foreign_key => :music_session_id, 
-    #            :inverse_of => :music_session_user_histories)
 
     def self.save(music_session_id, user_id, client_id)
       session_user_history = MusicSessionUserHistory.new()
@@ -48,5 +53,9 @@ module JamRuby
       hist.update_attribute(:session_removed_at, Time.now) if hist
     end
 
+    def perf_uri
+      self.perf_data.try(:uri)
+    end
+    
   end
 end