diff --git a/oml/downloads.py b/oml/downloads.py
index f15cf19..07c4a3d 100644
--- a/oml/downloads.py
+++ b/oml/downloads.py
@@ -26,13 +26,15 @@ class Downloads(Thread):
         self.transfers = SqliteDict(self._dbpath, tablename='transfers', autocommit=False)
 
     def download_updates(self):
-        now = int(time.mktime(time.gmtime()))
+        now = int(time.time())
         if now > settings.server.get('last_update_check', 0) + 24*60*60:
             settings.server['last_update_check'] = now
             update.download()
             state.user().export_library()
-            if settings.preferences.get('sendDiagnostics'):
-                utils.send_debug()
+        if settings.preferences.get('sendDiagnostics') and \
+              now > settings.server.get('last_send_diagnostics', 0) + 60*60:
+            utils.send_debug()
+            settings.server['last_send_diagnostics'] = now
 
     def download_next(self):
         import item.models
diff --git a/oml/utils.py b/oml/utils.py
index c8c3084..1ca978b 100644
--- a/oml/utils.py
+++ b/oml/utils.py
@@ -495,22 +495,25 @@ def send_debug():
         'User-Agent': settings.USER_AGENT,
     }
     debug_log = os.path.join(settings.data_path, 'debug.log')
+    last_debug = settings.server.get('last_debug')
+    old = last_debug is not None
     try:
         if os.path.exists(debug_log):
             data = []
-            today = datetime.now().strftime('%Y-%m-%d').encode()
-            old = True
-            with open(debug_log, 'rb') as fd:
+            with open(debug_log, 'r') as fd:
                 for line in fd:
-                    if line.startswith(today):
-                        old = False
+                    t = line.split(':DEBUG')[0]
+                    if t.count('-') == 2:
+                        timestamp = t
+                        if old and timestamp > last_debug:
+                            old = False
                     if not old:
                         data.append(line)
-                data = b'\n'.join(data)
+                data = '\n'.join(data)
             if data:
                 bytes_io = io.BytesIO()
                 gzip_file = gzip.GzipFile(fileobj=bytes_io, mode='wb')
-                gzip_file.write(data)
+                gzip_file.write(data.encode())
                 gzip_file.close()
                 result = bytes_io.getvalue()
                 bytes_io.close()
@@ -519,5 +522,7 @@ def send_debug():
                 r = opener.open(url, result)
                 if r.status != 200:
                     logger.debug('failed to send debug information')
+                else:
+                    settings.server['last_debug'] = timestamp
     except:
         logger.debug('failed to send debug information')