diff --git a/export_bg/models/export_bg_mixin.py b/export_bg/models/export_bg_mixin.py
index 96096902..50dee5ca 100644
--- a/export_bg/models/export_bg_mixin.py
+++ b/export_bg/models/export_bg_mixin.py
@@ -14,6 +14,8 @@ class DateTimeEncoder(json.JSONEncoder):
     def default(self, obj):
         if isinstance(obj, (datetime, date, time)):
             return obj.isoformat()
+        if isinstance(obj, (bytes, bytearray, memoryview)):
+            return base64.b64encode(bytes(obj)).decode()
         return super().default(obj)