diff --git a/htdocs/gfx/svg-defs.svg b/htdocs/gfx/svg-defs.svg
index e91a8bc..5ecb27f 100644
--- a/htdocs/gfx/svg-defs.svg
+++ b/htdocs/gfx/svg-defs.svg
@@ -12,5 +12,6 @@
         <g id="zoom-in-total" stroke="#fff"><circle cx="44.701" cy="51.307" r="16.326" fill="none" stroke-linecap="round" stroke-linejoin="round" stroke-width="4.75"/><path d="M59.779 60.356 72.3 72.877a2 2 90 0 1 0 2.829l-2.755 2.754a2 2-180 0 1-2.828 0L54.196 65.94" fill="#fff" stroke-width="1.247"/><path d="M4.8 1.244v33.801L17.595 21.7H62.4l12.793 13.346v-33.8L62.296 14.698H17.698z" fill="#fff"/></g>
         <g id="speaker" stroke="#fff"><path d="M33.5 7.15 16.74 25.201H2.65v31.7h16.041L33.5 72.848z" fill="#fff" stroke-width="2.1"/><g fill="none"><path d="M46.336 16.041A20 30 0 0 1 54.3 40a20 30 0 0 1-7.964 23.959" stroke-width="3"/><path d="M52.716 9.652A30.6 38 0 0 1 64.9 40a30.6 38 0 0 1-12.184 30.348" stroke-width="4.2"/><path d="M59.035 2.065A41.1 47.5 0 0 1 75.4 40a41.1 47.5 0 0 1-16.365 37.935" stroke-width="5.4"/></g></g>
         <g id="speaker-muted"><path d="M33.5 7.15 16.74 25.201H2.65v31.7h16.041L33.5 72.848z" fill="#fff" stroke="#fff" stroke-width="2.1"/></g>
+        <g id="waterfall-auto"><path d="M33.512 72.05s3.393-64.129 8.24-64.093c4.48.034 4.392 28.286 9.98 28.198 4.775-.074 5.279-13.721 6.33-17.88 1.013-4.004 2.915-5.172 5.321-4.894 2.993.346 8.205 5.925 10.588 13.761 4.16 13.677 5.53 44.907 5.53 44.907z" fill="#ccc" stroke="#ccc"/><path d="M29.3 68.8 18.4 54 7.5 68.8zM7.5 11.2 18.4 26l10.9-14.8zM18.4 26v28" fill="#fff" fill-opacity=".994" stroke="#fff" stroke-width="7.5"/></g>
     </defs>
 </svg>
\ No newline at end of file
diff --git a/htdocs/index.html b/htdocs/index.html
index d82e3d2..42072b3 100644
--- a/htdocs/index.html
+++ b/htdocs/index.html
@@ -135,7 +135,9 @@
                         <svg class="muted" viewBox="0 0 80 80"><use xlink:href="static/gfx/svg-defs.svg#speaker-muted"></use></svg>
                     </div>
                     <input title="Volume" id="openwebrx-panel-volume" class="openwebrx-panel-slider" type="range" min="0" max="150" value="50" step="1" onchange="updateVolume()" oninput="updateVolume()">
-                    <div title="Auto-adjust waterfall colors (right-click for continuous)" id="openwebrx-waterfall-colors-auto" class="openwebrx-button"><span class="sprite sprite-waterfall-auto openwebrx-sliderbtn-img"></span></div>
+                    <div title="Auto-adjust waterfall colors (right-click for continuous)" id="openwebrx-waterfall-colors-auto" class="openwebrx-button openwebrx-slider-button">
+                        <svg viewBox="0 0 80 80"><use xlink:href="static/gfx/svg-defs.svg#waterfall-auto"></use></svg>
+                    </div>
                     <input title="Waterfall minimum level" id="openwebrx-waterfall-color-min" class="openwebrx-panel-slider" type="range" min="-200" max="100" value="50" step="1" onchange="updateWaterfallColors(0);" oninput="updateVolume()">
                 </div>
                 <div class="openwebrx-panel-line">
diff --git a/inkscape files/openwebrx-waterfall-auto.svg b/inkscape files/openwebrx-waterfall-auto.svg
new file mode 100644
index 0000000..a98ccb6
--- /dev/null
+++ b/inkscape files/openwebrx-waterfall-auto.svg	
@@ -0,0 +1,119 @@
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+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:xlink="http://www.w3.org/1999/xlink"
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