diff --git a/USER_MANUAL.html b/USER_MANUAL.html
index 658611ea..f06ce964 100644
--- a/USER_MANUAL.html
+++ b/USER_MANUAL.html
@@ -643,7 +643,14 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 </tbody>
 </table>
 <h1 data-number="18" id="release-notes"><span class="header-section-number">18</span> Release Notes</h1>
-<h2 data-number="18.1" id="v1.9.9-april-2024"><span class="header-section-number">18.1</span> V1.9.9 April 2024</h2>
+<h2 data-number="18.1" id="v1.9.9.1-april-2024"><span class="header-section-number">18.1</span> V1.9.9.1 April 2024</h2>
+<ol type="1">
+<li>Bugfixes:
+<ul>
+<li>Revert PR #689 and reimplement fix for original startup delay issue. (PR #712)</li>
+</ul></li>
+</ol>
+<h2 data-number="18.2" id="v1.9.9-april-2024"><span class="header-section-number">18.2</span> V1.9.9 April 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -669,7 +676,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Add ability to build without LPCNet in preparation for potential future deprecation of 2020/2020B. (PR #711)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.2" id="v1.9.8-february-2024"><span class="header-section-number">18.2</span> V1.9.8 February 2024</h2>
+<h2 data-number="18.3" id="v1.9.8-february-2024"><span class="header-section-number">18.3</span> V1.9.8 February 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -696,21 +703,21 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Move FreeDV Reporter dialog code to dialogs section of codebase. (PR #664)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.3" id="v1.9.7.2-january-2024"><span class="header-section-number">18.3</span> V1.9.7.2 January 2024</h2>
+<h2 data-number="18.4" id="v1.9.7.2-january-2024"><span class="header-section-number">18.4</span> V1.9.7.2 January 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
 <li>Another attempt at fixing the crash previously thought to have been fixed by 1.9.7.1. (PR #659)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.4" id="v1.9.7.1-january-2024"><span class="header-section-number">18.4</span> V1.9.7.1 January 2024</h2>
+<h2 data-number="18.5" id="v1.9.7.1-january-2024"><span class="header-section-number">18.5</span> V1.9.7.1 January 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
 <li>Fix issue causing intermittent crashes when filters are enabled while running. (PR #656)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.5" id="v1.9.7-january-2024"><span class="header-section-number">18.5</span> V1.9.7 January 2024</h2>
+<h2 data-number="18.6" id="v1.9.7-january-2024"><span class="header-section-number">18.6</span> V1.9.7 January 2024</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -760,7 +767,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Remove no longer used scripts and patch files. (PR #654)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.6" id="v1.9.6-december-2023"><span class="header-section-number">18.6</span> V1.9.6 December 2023</h2>
+<h2 data-number="18.7" id="v1.9.6-december-2023"><span class="header-section-number">18.7</span> V1.9.6 December 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -781,7 +788,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Add 5368.5 kHz to the default frequency list. (PR #626)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.7" id="v1.9.5-november-2023"><span class="header-section-number">18.7</span> V1.9.5 November 2023</h2>
+<h2 data-number="18.8" id="v1.9.5-november-2023"><span class="header-section-number">18.8</span> V1.9.5 November 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -810,7 +817,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Report OS usage to FreeDV Reporter. (PR #606)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.8" id="v1.9.4-october-2023"><span class="header-section-number">18.8</span> V1.9.4 October 2023</h2>
+<h2 data-number="18.9" id="v1.9.4-october-2023"><span class="header-section-number">18.9</span> V1.9.4 October 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -828,7 +835,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 </ul></li>
 </ul></li>
 </ol>
-<h2 data-number="18.9" id="v1.9.3-october-2023"><span class="header-section-number">18.9</span> V1.9.3 October 2023</h2>
+<h2 data-number="18.10" id="v1.9.3-october-2023"><span class="header-section-number">18.10</span> V1.9.3 October 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -870,7 +877,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Refactor rig control handling to improve performance and maintainability. (PR #564)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.10" id="v1.9.2-september-2023"><span class="header-section-number">18.10</span> V1.9.2 September 2023</h2>
+<h2 data-number="18.11" id="v1.9.2-september-2023"><span class="header-section-number">18.11</span> V1.9.2 September 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -913,7 +920,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Remove unneeded 2400B and 2020B sample files. (PR #521)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.11" id="v1.9.1-august-2023"><span class="header-section-number">18.11</span> V1.9.1 August 2023</h2>
+<h2 data-number="18.12" id="v1.9.1-august-2023"><span class="header-section-number">18.12</span> V1.9.1 August 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -929,7 +936,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 <li>Add background coloring to indicate that the voice keyer is active. (PR #500)</li>
 </ul></li>
 </ol>
-<h2 data-number="18.12" id="v1.9.0-august-2023"><span class="header-section-number">18.12</span> V1.9.0 August 2023</h2>
+<h2 data-number="18.13" id="v1.9.0-august-2023"><span class="header-section-number">18.13</span> V1.9.0 August 2023</h2>
 <ol type="1">
 <li>Bugfixes:
 <ul>
@@ -964,7 +971,7 @@ FMA             -       Supports FMA extensions using YMM state</code></pre>
 </ul></li>
 </ol>
 <p><em>Note: Official Windows releases are now signed using Software Freedom Conservancy’s code certificate. To validate that the installers and binary files are properly signed, right-click on the file, choose Properties and go to the ‘Digital Signatures’ tab.</em></p>
-<h2 data-number="18.13" id="earlier-than-v1.9.0"><span class="header-section-number">18.13</span> Earlier than V1.9.0</h2>
+<h2 data-number="18.14" id="earlier-than-v1.9.0"><span class="header-section-number">18.14</span> Earlier than V1.9.0</h2>
 <p>See <a href="https://github.com/drowe67/codec2/blob/master/CHANGELOG_OLD.md">this</a> for more information about changes in versions prior to v1.9.0.</p>
 <h1 data-number="19" id="references"><span class="header-section-number">19</span> References</h1>
 <ul>
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