Unit test runner doesn't display accented characters

Another cosmetic issue...

I have an NUnit test that uses the TestCase attribute:

[TestCase("714020101012983", "Telefónica Móviles Panamá S.A. - Panama", "714", "020")]
public void TestLoadingOperatorList(string imsi, string operatorName, string mcc, string mnc)

When the test is executed in the test runner, the accented characters are not displayed as characters, but instead their raw hex values are shown.
See the attached screen shot.
(Just in case the accents are stripped in this forum, the 'o' character in 'Telefonica' has an acute accent.  This character is displayed as '\x00F3' in the test runner.)