diff --git a/include/iact_data/zfits_acada_data_source.hpp b/include/iact_data/zfits_acada_data_source.hpp
index 7a9792e4..5de4f7f0 100644
--- a/include/iact_data/zfits_acada_data_source.hpp
+++ b/include/iact_data/zfits_acada_data_source.hpp
@@ -94,7 +94,7 @@ class ZFITSSingleFileACADACameraEventDataSource:
   data_stream_type* get_data_stream() override;
 
   static config_type default_config();
-  const config_type& config() const { return config_; }
+  config_type config() const { return config_; }
 
 private:
   std::string filename_;
@@ -137,7 +137,7 @@ class ZFITSACADACameraEventDataSource:
   void set_next_index(uint64_t next_index) override;
 
   static config_type default_config();
-  const config_type& config() const { return config_; }
+  config_type config() const { return config_; }
 
 protected:
   using BaseDataSource::source_;
diff --git a/src/iact_data/parallel_event_dispatcher.cpp b/src/iact_data/parallel_event_dispatcher.cpp
index 4a40ea4b..f8d36d95 100644
--- a/src/iact_data/parallel_event_dispatcher.cpp
+++ b/src/iact_data/parallel_event_dispatcher.cpp
@@ -255,28 +255,33 @@ void ParallelEventDispatcher::
 process_cta_zfits_run(const std::string& filename,
   const calin::ix::iact_data::event_dispatcher::EventDispatcherConfig& config)
 {
-  CTAZFITSDataSource cta_file(filename, config.decoder(), config.zfits());
-  TelescopeRunConfiguration* run_config = cta_file.get_run_configuration();
+  auto* cta_file = new CTAZFITSDataSource (filename, config.decoder(), config.zfits());
+  TelescopeRunConfiguration* run_config = cta_file->get_run_configuration();
 
-  unsigned nfragments = cta_file.num_fragments();
+  unsigned nfragments = cta_file->num_fragments();
   unsigned nthread = std::min(std::max(config.nthread(), 1U), nfragments);
 
   if(nthread == 1) {
     try {
-      process_src(&cta_file, run_config, config.log_frequency());
+      process_src(cta_file, run_config, config.log_frequency());
     } catch(...) {
+      delete cta_file;
       delete run_config;
       throw;
     }
   } else {
+    auto* src_factory = new CTAZFITSDataSourceFactory(cta_file);
     try {
-      CTAZFITSDataSourceFactory src_factory(&cta_file);
-      process_src_factory(&src_factory, run_config, config.log_frequency(), nthread);
+      process_src_factory(src_factory, run_config, config.log_frequency(), nthread);
     } catch(...) {
+      delete src_factory;
+      delete cta_file;
       delete run_config;
       throw;
     }
+    delete src_factory;
   }
+  delete cta_file;
   delete run_config;
 }
 
diff --git a/src/iact_data/zfits_acada_data_source.cpp b/src/iact_data/zfits_acada_data_source.cpp
index a81d6c3b..6d5cd33f 100644
--- a/src/iact_data/zfits_acada_data_source.cpp
+++ b/src/iact_data/zfits_acada_data_source.cpp
@@ -482,29 +482,7 @@ ZFITSACADACameraEventDataSource(const std::string& filename, const config_type&
         filename, config), true),
   config_(config), run_header_(nullptr)
 {
-  if(source_) {
-    run_header_ = source_->get_run_header();
-    data_stream_ = source_->get_data_stream();
-  }
-  if((run_header_ == nullptr 
-      or (is_message_type<data_stream_type>() and data_stream_ == nullptr)) 
-    and opener_->num_sources() > 1) {
-    // In this case the first file fragment is missing the RunHeader or DataStream, search
-    // for it in later fragments then reopen the first fragment
-
-    while((run_header_ == nullptr or data_stream_ == nullptr) and isource_ < opener_->num_sources())
-    {
-      ++isource_;
-      open_file();
-      if(run_header_ == nullptr)
-        run_header_ = source_ ? source_->get_run_header() : nullptr;
-      if(data_stream_ == nullptr)
-        data_stream_ = source_ ? source_->get_data_stream() : nullptr;
-    }
-
-    isource_ = 0;
-    open_file();
-  }
+  // nothing to see here
 }
 
 template<typename MessageSet>
@@ -530,14 +508,14 @@ void ZFITSACADACameraEventDataSource<MessageSet>::load_run_header()
     }
     while((run_header_ == nullptr 
         or (is_message_type<data_stream_type>() and data_stream_ == nullptr)) 
-      and isource_<opener_->num_sources()-1)
+      and (isource_+1)<opener_->num_sources())
     {
       ++isource_;
       open_file();
-      if(run_header_ == nullptr)
-        run_header_ = source_ ? source_->get_run_header() : nullptr;
-      if(data_stream_ == nullptr)
-        data_stream_ = source_ ? source_->get_data_stream() : nullptr;
+      if(source_) {
+        if(run_header_ == nullptr)run_header_ = source_->get_run_header();
+        if(data_stream_ == nullptr)data_stream_ = source_->get_data_stream();
+      }
     }
     if(isource_ != saved_isource) {
       isource_ = saved_isource;