diff --git a/htdocs/gfx/svg-defs.svg b/htdocs/gfx/svg-defs.svg
index 8f7799b..a9bc05e 100644
--- a/htdocs/gfx/svg-defs.svg
+++ b/htdocs/gfx/svg-defs.svg
@@ -13,6 +13,7 @@
         <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" stroke="#fff" stroke-width="7.5"/></g>
+        <g id="waterfall-default"><path d="M36.356 75.295s3.187-34.502 7.74-34.482c4.207.018 4.125 15.218 9.374 15.171 4.485-.04 4.958-7.382 5.945-9.62.951-2.154 2.738-2.782 4.998-2.632 2.812.186 7.707 3.187 9.945 7.403 3.906 7.358 5.193 24.16 5.193 24.16z" fill="#ccc" stroke="#ccc" stroke-width=".711"/><path d="M18.4 25.424v29.075m-10.9 0L18.4 69.3l10.9-14.801zm10.9-43.875L7.5 25.425h21.801z" fill="#fff" stroke="#fff" stroke-width="7.5"/></g>
         <g id="squelch" fill="#fff" stroke-width=".767"><path d="M33.333 24.7c-.058-14.132-5.913-21.9-16.58-21.9-10.145 0-16 7.673-16 20.963 0 10.575 3.305 15.722 11.884 18.343l5.913 1.872c5.797 1.778 7.942 4.399 7.942 9.92 0 5.71-3.246 9.172-8.521 9.172-5.913 0-9.218-4.024-9.508-11.324H0C.521 66.345 6.724 74.3 17.506 74.3c10.899 0 17.333-8.142 17.333-22.087 0-10.762-3.362-16.378-11.188-18.81l-6.609-2.06c-6.203-1.965-8-3.93-8-8.89 0-5.148 2.782-8.423 7.304-8.423 5.507 0 8.58 3.743 8.87 10.669zM75.362 62.508C78.202 56.893 80 47.534 80 38.363c0-10.014-2.203-19.653-5.913-26.11C70.435 5.887 65.681 2.8 59.653 2.8S48.87 5.888 45.218 12.252C41.45 18.71 39.305 28.35 39.305 38.55s2.203 19.84 5.913 26.298c3.652 6.364 8.406 9.452 14.435 9.452 4.405 0 7.594-1.404 10.956-4.68l4.986 7.581L80 69.621zM64.638 46.13l-4.406 7.58 4.464 6.833c-1.391 1.123-3.246 1.778-5.101 1.778C52.638 62.321 48 52.869 48 38.549c0-14.412 4.58-23.771 11.652-23.771s11.652 9.358 11.652 23.864c0 5.615-.638 10.67-1.913 14.787z"/></g>
     </defs>
 </svg>
\ No newline at end of file
diff --git a/htdocs/index.html b/htdocs/index.html
index 84139d4..16220d3 100644
--- a/htdocs/index.html
+++ b/htdocs/index.html
@@ -145,7 +145,9 @@
                         <svg viewBox="0 0 80 80"><use xlink:href="static/gfx/svg-defs.svg#squelch"></use></svg>
                     </div>
                     <input title="Squelch" class="openwebrx-squelch-slider openwebrx-panel-slider" type="range" min="-150" max="0" value="-150" step="1">
-                    <div title="Set waterfall colors to default" id="openwebrx-waterfall-colors-default" class="openwebrx-button" onclick="waterfallColorsDefault()"><span class="sprite sprite-waterfall-default openwebrx-sliderbtn-img"></span></div>
+                    <div title="Set waterfall colors to default" id="openwebrx-waterfall-colors-default" class="openwebrx-button openwebrx-slider-button" onclick="waterfallColorsDefault()">
+                        <svg viewBox="0 0 80 80"><use xlink:href="static/gfx/svg-defs.svg#waterfall-default"></use></svg>
+                    </div>
                     <input title="Waterfall maximum level" id="openwebrx-waterfall-color-max" class="openwebrx-panel-slider" type="range" min="-200" max="100" value="50" step="1" onchange="updateWaterfallColors(1);" oninput="updateVolume()">
                 </div>
                 <div class="openwebrx-panel-line">
diff --git a/inkscape files/openwebrx-waterfall-default.svg b/inkscape files/openwebrx-waterfall-default.svg
new file mode 100644
index 0000000..51b5beb
--- /dev/null
+++ b/inkscape files/openwebrx-waterfall-default.svg	
@@ -0,0 +1,123 @@
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+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:xlink="http://www.w3.org/1999/xlink"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="80"
+   height="80"
+   viewBox="0 0 80 80"
+   version="1.1"
+   id="svg2431"
+   sodipodi:docname="openwebrx-waterfall-default.svg"
+   inkscape:version="1.0.2 (e86c870879, 2021-01-15, custom)">
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+        <dc:type
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+        <dc:title></dc:title>
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