diff --git a/src/contacts/Contact.cpp b/src/contacts/Contact.cpp
index 084e7f72..e927b3e3 100644
--- a/src/contacts/Contact.cpp
+++ b/src/contacts/Contact.cpp
@@ -338,8 +338,8 @@ QDataStream &operator>>(QDataStream &in, Contact &contact)
     BlockInfo blockInfo;
     QList<Contact::PhoneNumber> phoneNumbers;
 
-    in >> id >> dn >> sourceUid >> name >> prio >> displayName >> company >> mail >> lastModified
-            >> sipStatusSubscriptable >> phoneNumbers >> blockInfo;
+    in >> id >> dn >> sourceUid >> name >> prio >> displayName >> configId >> company >> mail
+            >> lastModified >> sipStatusSubscriptable >> phoneNumbers >> blockInfo;
     contact = Contact(id, dn, sourceUid, { prio, displayName, configId }, name, company, mail,
                       lastModified, phoneNumbers, blockInfo);
 
diff --git a/src/contacts/carddav/CardDAVAddressBookFeeder.cpp b/src/contacts/carddav/CardDAVAddressBookFeeder.cpp
index 74635e92..dae8fa1d 100644
--- a/src/contacts/carddav/CardDAVAddressBookFeeder.cpp
+++ b/src/contacts/carddav/CardDAVAddressBookFeeder.cpp
@@ -219,18 +219,29 @@ void CardDAVAddressBookFeeder::loadCachedData(const size_t hash)
 
     QDataStream in(&cacheFile);
 
-    quint16 magic;
-    quint8 version;
-    qsizetype numberOfContacts;
+    quint16 magic = 0;
+    quint8 version = 0;
 
     in >> magic;
     in >> version;
-    in >> m_ignoredIds;
-    in >> numberOfContacts;
 
-    if (magic != CARDDAV_MAGIC || version != CARDDAV_VERSION) {
+    if (in.status() != QDataStream::Ok || magic != CARDDAV_MAGIC || version != CARDDAV_VERSION) {
         qCInfo(lcCardDAVAddressBookFeeder) << "CardDAV cache file at" << filePath
                                            << "is invalid and will therefore be removed.";
+        cacheFile.close();
+        cacheFile.remove();
+        return;
+    }
+
+    qsizetype numberOfContacts = 0;
+    in >> m_ignoredIds;
+    in >> numberOfContacts;
+
+    if (in.status() != QDataStream::Ok || numberOfContacts < 0 || numberOfContacts > 1000000) {
+        qCWarning(lcCardDAVAddressBookFeeder) << "CardDAV cache file at" << filePath
+                                              << "is corrupted and will therefore be removed.";
+        m_ignoredIds.clear();
+        cacheFile.close();
         cacheFile.remove();
         return;
     }
@@ -240,6 +251,20 @@ void CardDAVAddressBookFeeder::loadCachedData(const size_t hash)
         Contact *contact = new Contact(this);
         in >> key;
         in >> *contact;
+
+        if (in.status() != QDataStream::Ok) {
+            delete contact;
+            qCWarning(lcCardDAVAddressBookFeeder)
+                    << "CardDAV cache file at" << filePath
+                    << "is truncated or corrupted - aborting cache load.";
+            qDeleteAll(m_cachedContacts);
+            m_cachedContacts.clear();
+            m_ignoredIds.clear();
+            cacheFile.close();
+            cacheFile.remove();
+            return;
+        }
+
         m_cachedContacts.insert(key, contact);
     }
 
diff --git a/src/media/AudioPort.cpp b/src/media/AudioPort.cpp
index 1a713bbd..e3e0049f 100644
--- a/src/media/AudioPort.cpp
+++ b/src/media/AudioPort.cpp
@@ -35,7 +35,11 @@ bool AudioPort::initialize()
     createPort(m_device.id().toStdString(), m_pj_fmt);
 
     if (m_device.mode() == QAudioDevice::Mode::Input) {
-        adjustTxLevel(NORMAL_AUDIO_LEVEL);
+        try {
+            adjustTxLevel(NORMAL_AUDIO_LEVEL);
+        } catch (pj::Error &err) {
+            qCCritical(lcAudioPort) << "failed to adjust tx level: " << err.info();
+        }
     }
 
     return true;
@@ -45,7 +49,11 @@ void AudioPort::setMuted(bool value)
 {
     if (m_isMuted != value) {
         if (m_device.mode() == QAudioDevice::Mode::Input) {
-            adjustTxLevel(value ? 0.0f : NORMAL_AUDIO_LEVEL);
+            try {
+                adjustTxLevel(value ? 0.0f : NORMAL_AUDIO_LEVEL);
+            } catch (pj::Error &err) {
+                qCCritical(lcAudioPort) << "failed to adjust tx level: " << err.info();
+            }
         }
 
         m_isMuted = value;
@@ -166,8 +174,8 @@ void AudioPort::startSinkIO()
 
     qCInfo(lcAudioPort).noquote().nospace()
             << "Initialize sink of device_descr=\"" << m_device.description() << "\", device_id=\""
-            << m_device.id() << "\", with settings:"
-            << "\nsampleRate=" << m_audioFormat.sampleRate()
+            << m_device.id()
+            << "\", with settings:" << "\nsampleRate=" << m_audioFormat.sampleRate()
             << "\nchannelCount=" << m_audioFormat.channelCount()
             << "\nbytesPerSample=" << m_audioFormat.bytesPerSample()
             << "\nsampleFormat=" << m_audioFormat.sampleFormat();
@@ -208,8 +216,8 @@ void AudioPort::startSourceIO()
 
     qCInfo(lcAudioPort).noquote().nospace()
             << "Initialize source of device_descr=\"" << m_device.description()
-            << "\", device_id=\"" << m_device.id() << "\", with settings:"
-            << "\nsampleRate=" << m_audioFormat.sampleRate()
+            << "\", device_id=\"" << m_device.id()
+            << "\", with settings:" << "\nsampleRate=" << m_audioFormat.sampleRate()
             << "\nchannelCount=" << m_audioFormat.channelCount()
             << "\nbytesPerSample=" << m_audioFormat.bytesPerSample()
             << "\nsampleFormat=" << m_audioFormat.sampleFormat();
diff --git a/src/sip/SIPCall.cpp b/src/sip/SIPCall.cpp
index 8b30f53c..a4274e8e 100644
--- a/src/sip/SIPCall.cpp
+++ b/src/sip/SIPCall.cpp
@@ -20,6 +20,7 @@
 #include "NotificationManager.h"
 #include "AvatarManager.h"
 #include "GlobalCallState.h"
+#include "ErrorBus.h"
 
 #include <pjsua-lib/pjsua.h>
 #include <pjsua-lib/pjsua_internal.h>
@@ -159,8 +160,8 @@ void SIPCall::onCallState(pj::OnCallStateParam &prm)
     qCInfo(lcSIPCall).nospace() << "Call State: " << ci.stateText << " (" << remoteUri << ")"
                                 << " last status code: "
                                 << EnumTranslation::instance().sipStatusCode(statusCode) << " ("
-                                << statusCode << ") "
-                                << " last reason " << ci.lastReason << " contactId " << m_contactId;
+                                << statusCode << ") " << " last reason " << ci.lastReason
+                                << " contactId " << m_contactId;
 
     if (statusCode == PJSIP_SC_RINGING) {
         ringToneFactory.ringingTone()->start();
@@ -359,13 +360,35 @@ void SIPCall::onCallMediaState(pj::OnCallMediaStateParam &prm)
 
                     qCInfo(lcSIPCall) << "Found media, index" << i << "of" << ci.media.size();
                     aud_med = getAudioMedia(i);
-                    mic_media.startTransmit(aud_med);
-                    aud_med.startTransmit(speaker_media);
+
+                    try {
+                        mic_media.startTransmit(aud_med);
+                    } catch (pj::Error &err) {
+                        qCCritical(lcSIPCall)
+                                << "failed to start mic media transmission: " << err.info();
+                        ErrorBus::instance().addFatalError(
+                                tr("Failed to initialize microphone audio"));
+                    }
+
+                    try {
+                        aud_med.startTransmit(speaker_media);
+                    } catch (pj::Error &err) {
+                        qCCritical(lcSIPCall)
+                                << "failed to start aud media transmission: " << err.info();
+                        ErrorBus::instance().addFatalError(tr("Failed to initialize call audio"));
+                    }
 
                     if (!m_sniffer) {
                         m_sniffer = new Sniffer(this);
                         m_sniffer->initialize();
-                        aud_med.startTransmit(dynamic_cast<pj::AudioMediaPort &>(*m_sniffer));
+
+                        try {
+                            aud_med.startTransmit(dynamic_cast<pj::AudioMediaPort &>(*m_sniffer));
+                        } catch (pj::Error &err) {
+                            qCCritical(lcSIPCall)
+                                    << "failed to start audio level transmission: " << err.info();
+                        }
+
                         connect(m_sniffer, &Sniffer::audioLevelChanged, this, [this]() {
                             Q_EMIT SIPCallManager::instance().audioLevelChanged(
                                     this, m_sniffer->audioLevel());