diff --git a/htdocs/lib/BookmarkBar.js b/htdocs/lib/BookmarkBar.js
index 4edac8e..d039494 100644
--- a/htdocs/lib/BookmarkBar.js
+++ b/htdocs/lib/BookmarkBar.js
@@ -9,7 +9,7 @@ function BookmarkBar() {
         me.$container.find('.bookmark').removeClass('selected');
         var b = $bookmark.data();
         if (!b || !b.frequency || (!b.modulation && !b.digital_modulation)) return;
-        demodulator_set_offset_frequency(0, b.frequency - center_freq);
+        demodulators[0].set_offset_frequency(b.frequency - center_freq);
         if (b.modulation) {
             demodulator_analog_replace(b.modulation);
         } else if (b.digital_modulation) {
diff --git a/htdocs/openwebrx.js b/htdocs/openwebrx.js
index 45112f8..50cfdec 100644
--- a/htdocs/openwebrx.js
+++ b/htdocs/openwebrx.js
@@ -334,7 +334,6 @@ function demod_envelope_where_clicked(x, drag_ranges, key_modifiers) {  // Check
 //******* class Demodulator *******
 // this can be used as a base class for ANY demodulator
 Demodulator = function (offset_frequency) {
-    //console.log("this too");
     this.offset_frequency = offset_frequency;
     this.envelope = {};
     this.color = demodulators_get_next_color();
@@ -357,11 +356,7 @@ Demodulator.draggable_ranges = {
 
 demodulator_response_time = 50;
 
-//in ms; if we don't limit the number of SETs sent to the server, audio will underrun (possibly output buffer is cleared on SETs in GNU Radio
-
 function Demodulator_default_analog(offset_frequency, subtype) {
-    //console.log("hopefully this happens");
-    //http://stackoverflow.com/questions/4152931/javascript-inheritance-call-super-constructor-or-use-prototype-chain
     Demodulator.call(this, offset_frequency);
     this.subtype = subtype;
     this.filter = {
@@ -565,10 +560,10 @@ function demodulator_analog_replace(subtype, for_digital) { //this function shou
     update_digitalvoice_panels("openwebrx-panel-metadata-" + subtype);
 }
 
-function demodulator_set_offset_frequency(to_what) {
+Demodulator.prototype.set_offset_frequency = function(to_what) {
     if (to_what > bandwidth / 2 || to_what < -bandwidth / 2) return;
-    demodulators[0].offset_frequency = Math.round(to_what);
-    demodulators[0].set();
+    this.offset_frequency = Math.round(to_what);
+    this.set();
     mkenvelopes(get_visible_freq_range());
     tunedFrequencyDisplay.setFrequency(center_freq + to_what);
 }
@@ -635,7 +630,7 @@ function scale_canvas_mousemove(evt) {
     else if (scale_canvas_drag_params.drag) {
         //call the drag_move for all demodulators (and they will decide if they're dragged)
         for (i = 0; i < demodulators.length; i++) event_handled |= demodulators[i].envelope.drag_move(evt.pageX);
-        if (!event_handled) demodulator_set_offset_frequency(scale_offset_freq_from_px(evt.pageX));
+        if (!event_handled) demodulators[0].set_offset_frequency(scale_offset_freq_from_px(evt.pageX));
     }
 
 }
@@ -651,7 +646,7 @@ function scale_canvas_end_drag(x) {
     scale_canvas_drag_params.mouse_down = false;
     var event_handled = false;
     for (var i = 0; i < demodulators.length; i++) event_handled |= demodulators[i].envelope.drag_end();
-    if (!event_handled) demodulator_set_offset_frequency(scale_offset_freq_from_px(x));
+    if (!event_handled) demodulators[0].set_offset_frequency(scale_offset_freq_from_px(x));
 }
 
 function scale_canvas_mouseup(evt) {
@@ -932,7 +927,7 @@ function canvas_mouseup(evt) {
     var relativeX = get_relative_x(evt);
 
     if (!canvas_drag) {
-        demodulator_set_offset_frequency(canvas_get_freq_offset(relativeX));
+        demodulators[0].set_offset_frequency(canvas_get_freq_offset(relativeX));
     }
     else {
         canvas_end_drag();
@@ -1792,7 +1787,7 @@ function openwebrx_init() {
     initPanels();
     tunedFrequencyDisplay = new TuneableFrequencyDisplay($('#webrx-actual-freq'));
     tunedFrequencyDisplay.onFrequencyChange(function(f) {
-        demodulator_set_offset_frequency(f - center_freq);
+        demodulators[0].set_offset_frequency(f - center_freq);
     });
     mouseFrequencyDisplay = new FrequencyDisplay($('#webrx-mouse-freq'));
     window.addEventListener("resize", openwebrx_resize);