diff --git a/aegisub/libaegisub/include/libaegisub/signal.h b/aegisub/libaegisub/include/libaegisub/signal.h
index 35dd22248..fe9d3b6bc 100644
--- a/aegisub/libaegisub/include/libaegisub/signal.h
+++ b/aegisub/libaegisub/include/libaegisub/signal.h
@@ -215,6 +215,18 @@ public:
 	UnscopedConnection Connect(void (T::*func)(Arg1, Arg2), T* a1) {
 		return Connect(std::bind(func, a1, _1, _2));
 	}
+
+	/// @brief Connect a member function with the correct signature to this signal
+	/// @param func Function to connect
+	/// @param a1   Object
+	///
+	/// This overload is purely for convenience so that classes can do
+	/// sig.Connect(&Class::Foo, this) rather than
+	/// sig.Connect(&Class::Foo, this, _1)
+	template<class T>
+	UnscopedConnection Connect(void (T::*func)(Arg1), T* a1) {
+		return Connect(std::bind(func, a1, _1));
+	}
 };
 
 /// @class Signal
diff --git a/aegisub/src/ass_file.cpp b/aegisub/src/ass_file.cpp
index 133eb55dc..7cdb1741e 100644
--- a/aegisub/src/ass_file.cpp
+++ b/aegisub/src/ass_file.cpp
@@ -372,6 +372,10 @@ void AssFile::AddToRecent(wxString const& file) const {
 }
 
 int AssFile::Commit(wxString const& desc, int type, int amendId, AssEntry *single_line) {
+	std::set<const AssEntry*> changed_lines;
+	if (single_line)
+		changed_lines.insert(single_line);
+
 	++commitId;
 	// Allow coalescing only if it's the last change and the file has not been
 	// saved since the last change
@@ -389,7 +393,7 @@ int AssFile::Commit(wxString const& desc, int type, int amendId, AssEntry *singl
 		else {
 			UndoStack.back() = *this;
 		}
-		AnnounceCommit(type);
+		AnnounceCommit(type, changed_lines);
 		return commitId;
 	}
 
@@ -408,7 +412,7 @@ int AssFile::Commit(wxString const& desc, int type, int amendId, AssEntry *singl
 	if (UndoStack.size() > 1 && OPT_GET("App/Auto/Save on Every Change")->GetBool() && !filename.empty() && CanSave())
 		Save(filename);
 
-	AnnounceCommit(type);
+	AnnounceCommit(type, changed_lines);
 	return commitId;
 }
 
@@ -420,7 +424,7 @@ void AssFile::Undo() {
 	UndoStack.pop_back();
 	*this = UndoStack.back();
 
-	AnnounceCommit(COMMIT_NEW);
+	AnnounceCommit(COMMIT_NEW, std::set<const AssEntry*>());
 }
 
 void AssFile::Redo() {
@@ -430,7 +434,7 @@ void AssFile::Redo() {
 	UndoStack.push_back(*this);
 	RedoStack.pop_back();
 
-	AnnounceCommit(COMMIT_NEW);
+	AnnounceCommit(COMMIT_NEW, std::set<const AssEntry*>());
 }
 
 wxString AssFile::GetUndoDescription() const {
diff --git a/aegisub/src/ass_file.h b/aegisub/src/ass_file.h
index 268dbebef..165126148 100644
--- a/aegisub/src/ass_file.h
+++ b/aegisub/src/ass_file.h
@@ -33,14 +33,12 @@
 ///
 
 #include <boost/container/list.hpp>
-
+#include <boost/intrusive/list.hpp>
 #include <set>
 #include <vector>
 
 #include <wx/arrstr.h>
 
-#include <boost/intrusive/list.hpp>
-
 #include <libaegisub/signal.h>
 
 #include "ass_entry.h"
@@ -65,7 +63,7 @@ class AssFile {
 	int autosavedCommitId;
 
 	/// A set of changes has been committed to the file (AssFile::CommitType)
-	agi::signal::Signal<int> AnnounceCommit;
+	agi::signal::Signal<int, std::set<const AssEntry*> const&> AnnounceCommit;
 	/// A new file has been opened (filename)
 	agi::signal::Signal<wxString> FileOpen;
 	/// The file is about to be saved
diff --git a/aegisub/src/audio_karaoke.cpp b/aegisub/src/audio_karaoke.cpp
index a6674d5c5..5ea4939e3 100644
--- a/aegisub/src/audio_karaoke.cpp
+++ b/aegisub/src/audio_karaoke.cpp
@@ -118,8 +118,8 @@ void AudioKaraoke::OnActiveLineChanged(AssDialogue *new_line) {
 	}
 }
 
-void AudioKaraoke::OnFileChanged(int type) {
-	if (enabled && (type & AssFile::COMMIT_DIAG_FULL)) {
+void AudioKaraoke::OnFileChanged(int type, std::set<const AssEntry *> const& changed) {
+	if (enabled && (type & AssFile::COMMIT_DIAG_FULL) && (changed.empty() || changed.count(active_line))) {
 		LoadFromLine();
 		split_area->Refresh(false);
 	}
diff --git a/aegisub/src/audio_karaoke.h b/aegisub/src/audio_karaoke.h
index c4a769b30..0f5483a1c 100644
--- a/aegisub/src/audio_karaoke.h
+++ b/aegisub/src/audio_karaoke.h
@@ -30,6 +30,7 @@
 #include <libaegisub/signal.h>
 
 class AssDialogue;
+class AssEntry;
 class AssKaraoke;
 class wxButton;
 
@@ -136,7 +137,7 @@ class AudioKaraoke : public wxWindow {
 	void OnActiveLineChanged(AssDialogue *new_line);
 	void OnContextMenu(wxContextMenuEvent&);
 	void OnEnableButton(wxCommandEvent &evt);
-	void OnFileChanged(int type);
+	void OnFileChanged(int type, std::set<const AssEntry *> const& changed);
 	void OnMouse(wxMouseEvent &event);
 	void OnPaint(wxPaintEvent &event);
 	void OnSize(wxSizeEvent &event);