diff --git a/python/src/trezorlib/protobuf.py b/python/src/trezorlib/protobuf.py
index 645a94519..d14741be0 100644
--- a/python/src/trezorlib/protobuf.py
+++ b/python/src/trezorlib/protobuf.py
@@ -161,7 +161,7 @@ class EnumType:
     def validate(self, fvalue: int) -> int:
         if fvalue not in self.enum_values:
             # raise TypeError("Invalid enum value")
-            LOG.warning("Value {} unknown for type {}".format(fvalue, self.enum_name))
+            LOG.info("Value {} unknown for type {}".format(fvalue, self.enum_name))
         return fvalue
 
     def to_str(self, fvalue: int) -> str:
@@ -485,7 +485,10 @@ def format_message(
             return "{} bytes {}{}".format(length, output, suffix)
 
         if isinstance(value, int) and isinstance(ftype, EnumType):
-            return "{} ({})".format(ftype.to_str(value), value)
+            try:
+                return "{} ({})".format(ftype.to_str(value), value)
+            except TypeError:
+                return str(value)
 
         return repr(value)
 
@@ -558,7 +561,10 @@ def to_dict(msg: MessageType, hexlify_bytes: bool = True) -> Dict[str, Any]:
         elif isinstance(value, list):
             return [convert_value(ftype, v) for v in value]
         elif isinstance(value, int) and isinstance(ftype, EnumType):
-            return ftype.to_str(value)
+            try:
+                return ftype.to_str(value)
+            except TypeError:
+                return value
         else:
             return value
 
diff --git a/python/tests/test_protobuf_encoding.py b/python/tests/test_protobuf_encoding.py
index 8108fdc54..7d7709f28 100644
--- a/python/tests/test_protobuf_encoding.py
+++ b/python/tests/test_protobuf_encoding.py
@@ -15,6 +15,7 @@
 # If not, see <https://www.gnu.org/licenses/lgpl-3.0.html>.
 
 from io import BytesIO
+import logging
 
 import pytest
 
@@ -137,6 +138,7 @@ def test_simple_message():
 
 
 def test_validate_enum(caplog):
+    caplog.set_level(logging.INFO)
     # round-trip of a valid value
     msg = EnumMessageMoreValues(enum=0)
     buf = BytesIO()
@@ -154,7 +156,7 @@ def test_validate_enum(caplog):
 
     assert len(caplog.records) == 1
     record = caplog.records.pop(0)
-    assert record.levelname == "WARNING"
+    assert record.levelname == "INFO"
     assert record.getMessage() == "Value 19 unknown for type t"
 
     msg.enum = 3
@@ -165,7 +167,7 @@ def test_validate_enum(caplog):
 
     assert len(caplog.records) == 1
     record = caplog.records.pop(0)
-    assert record.levelname == "WARNING"
+    assert record.levelname == "INFO"
     assert record.getMessage() == "Value 3 unknown for type t"
 
 
@@ -182,12 +184,14 @@ def test_repeated():
 
 
 def test_enum_in_repeated(caplog):
+    caplog.set_level(logging.INFO)
+
     msg = RepeatedFields(enumlist=[0, 1, 2, 3])
     buf = BytesIO()
     protobuf.dump_message(buf, msg)
     assert len(caplog.records) == 2
     for record in caplog.records:
-        assert record.levelname == "WARNING"
+        assert record.levelname == "INFO"
         assert "unknown for type t" in record.getMessage()
 
 
diff --git a/python/tests/test_protobuf_misc.py b/python/tests/test_protobuf_misc.py
index 1ff38a5bb..73d6efd44 100644
--- a/python/tests/test_protobuf_misc.py
+++ b/python/tests/test_protobuf_misc.py
@@ -216,3 +216,21 @@ def test_nested_recover():
     dictdata = {"nested": {}}
     recovered = protobuf.dict_to_proto(NestedMessage, dictdata)
     assert isinstance(recovered.nested, SimpleMessage)
+
+
+@with_simple_enum
+def test_unknown_enum_to_str():
+    simple = SimpleMessage(enum=SimpleEnum.QUUX)
+    string = protobuf.format_message(simple)
+    assert "enum: QUUX (13)" in string
+
+    simple = SimpleMessage(enum=6000)
+    string = protobuf.format_message(simple)
+    assert "enum: 6000" in string
+
+
+@with_simple_enum
+def test_unknown_enum_to_dict():
+    simple = SimpleMessage(enum=6000)
+    converted = protobuf.to_dict(simple)
+    assert converted["enum"] == 6000