diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 048f1501..a5b83a91 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -15,6 +15,7 @@ lib_xua Change Log
   * RESOLVED:  wChannelConfig in UAC1 descriptor set according to output channel
     count
   * RESOLVED:  Indexing of ADAT channel strings (#18059)
+  * RESOLVED:  Rebooting device fails when PLL config "not reset" bit is set 
 
   * Changes to dependencies:
 
diff --git a/lib_xua/src/core/support/reboot.xc b/lib_xua/src/core/support/reboot.xc
index 280b0b44..fbc11f6c 100644
--- a/lib_xua/src/core/support/reboot.xc
+++ b/lib_xua/src/core/support/reboot.xc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011-2018, XMOS Ltd, All rights reserved
+// Copyright (c) 2011-2019, XMOS Ltd, All rights reserved
 #include <xs1.h>
 #include <platform.h>
 #include <print.h>
@@ -12,7 +12,7 @@
 #if (XUD_SERIES_SUPPORT == 4)
 #include "xs2_su_registers.h"
 #define XS2_SU_PERIPH_USB_ID 0x1
-#define PLL_MASK 0x7FFFFFFF
+#define PLL_MASK 0x3FFFFFFF
 #else
 #define PLL_MASK 0xFFFFFFFF
 #endif
diff --git a/lib_xua/wscript b/lib_xua/wscript
index d34fd99a..76f039b3 100644
--- a/lib_xua/wscript
+++ b/lib_xua/wscript
@@ -106,4 +106,4 @@ def use_module(bld):
         depends_on=module_build_info['DEPENDENT_MODULES'],
         includes=module_build_info['INCLUDE_DIRS'],
         optional_headers=module_build_info['OPTIONAL_HEADERS'],
-        version=module_build_info['VERSION'])
+        version=module_build_info['VERSION'])
\ No newline at end of file