diff --git a/qtfred/src/mission/dialogs/CampaignEditorDialogModel.cpp b/qtfred/src/mission/dialogs/CampaignEditorDialogModel.cpp
index 546dcc74412..5e4b38e7164 100644
--- a/qtfred/src/mission/dialogs/CampaignEditorDialogModel.cpp
+++ b/qtfred/src/mission/dialogs/CampaignEditorDialogModel.cpp
@@ -441,7 +441,7 @@ void CampaignEditorDialogModel::sortMissions()
 
 void CampaignEditorDialogModel::stopSpeech()
 {
-	if (_waveId >= -1) {
+	if (_waveId >= 0) {
 		audiostream_close_file(_waveId, false);
 		_waveId = -1;
 	}
diff --git a/qtfred/src/mission/dialogs/CampaignEditorDialogModel.h b/qtfred/src/mission/dialogs/CampaignEditorDialogModel.h
index c8fb6271b6c..f0ab4040a4a 100644
--- a/qtfred/src/mission/dialogs/CampaignEditorDialogModel.h
+++ b/qtfred/src/mission/dialogs/CampaignEditorDialogModel.h
@@ -198,7 +198,7 @@ class CampaignEditorDialogModel : public AbstractDialogModel {
 	int m_current_mission_index = -1;
 	int m_current_branch_index = -1;
 
-	int _waveId;
+	int _waveId = -1;
 
 	CampaignFormat m_save_format = CampaignFormat::FSO;
 
diff --git a/qtfred/src/mission/dialogs/CommandBriefingDialogModel.cpp b/qtfred/src/mission/dialogs/CommandBriefingDialogModel.cpp
index 28144d30f78..46876471b84 100644
--- a/qtfred/src/mission/dialogs/CommandBriefingDialogModel.cpp
+++ b/qtfred/src/mission/dialogs/CommandBriefingDialogModel.cpp
@@ -180,7 +180,7 @@ bool CommandBriefingDialogModel::getMissionIsMultiTeam()
 
 void CommandBriefingDialogModel::stopSpeech()
 {
-	if (_waveId >= -1) {
+	if (_waveId >= 0) {
 		audiostream_close_file(_waveId, false);
 		_waveId = -1;
 	}
diff --git a/qtfred/src/mission/dialogs/CommandBriefingDialogModel.h b/qtfred/src/mission/dialogs/CommandBriefingDialogModel.h
index 11d7ad980cd..7e46df5548d 100644
--- a/qtfred/src/mission/dialogs/CommandBriefingDialogModel.h
+++ b/qtfred/src/mission/dialogs/CommandBriefingDialogModel.h
@@ -50,7 +50,7 @@ class CommandBriefingDialogModel: public AbstractDialogModel {
 	cmd_brief _wipCommandBrief[MAX_TVT_TEAMS];
 	int _currentTeam;
 	int _currentStage;
-	int _waveId;
+	int _waveId = -1;
 	SCP_vector<std::pair<SCP_string, int>> _teamList;
 };
 
diff --git a/qtfred/src/mission/dialogs/DebriefingDialogModel.cpp b/qtfred/src/mission/dialogs/DebriefingDialogModel.cpp
index fc03d19a308..8b8932cf8ea 100644
--- a/qtfred/src/mission/dialogs/DebriefingDialogModel.cpp
+++ b/qtfred/src/mission/dialogs/DebriefingDialogModel.cpp
@@ -289,7 +289,7 @@ bool DebriefingDialogModel::getMissionIsMultiTeam()
 
 void DebriefingDialogModel::stopSpeech()
 {
-	if (_waveId >= -1) {
+	if (_waveId >= 0) {
 		audiostream_close_file(_waveId, false);
 		_waveId = -1;
 	}
diff --git a/qtfred/src/mission/dialogs/DebriefingDialogModel.h b/qtfred/src/mission/dialogs/DebriefingDialogModel.h
index 6fd4f5505c8..3be37cccbbd 100644
--- a/qtfred/src/mission/dialogs/DebriefingDialogModel.h
+++ b/qtfred/src/mission/dialogs/DebriefingDialogModel.h
@@ -66,7 +66,7 @@ class DebriefingDialogModel: public AbstractDialogModel {
 
 	int _currentTeam;
 	int _currentStage;
-	int _waveId;
+	int _waveId = -1;
 	SCP_vector<std::pair<SCP_string, int>> _teamList;
 };