diff --git a/format/mp4/pssh_playready.go b/format/mp4/pssh_playready.go
index b6587561..63228c84 100644
--- a/format/mp4/pssh_playready.go
+++ b/format/mp4/pssh_playready.go
@@ -22,8 +22,8 @@ const (
 )
 
 var recordTypeNames = scalar.UintMapSymStr{
-	recordTypeRightsManagementHeader: "Rights management header",
-	recordTypeLicenseStore:           "License store",
+	recordTypeRightsManagementHeader: "rights_management_header",
+	recordTypeLicenseStore:           "license_store",
 }
 
 func playreadyPsshDecode(d *decode.D) any {
diff --git a/format/mp4/testdata/pssh.fqtest b/format/mp4/testdata/pssh.fqtest
index c20ebdc4..d6ce1d1d 100644
--- a/format/mp4/testdata/pssh.fqtest
+++ b/format/mp4/testdata/pssh.fqtest
@@ -25,7 +25,7 @@ $ fq ddv pssh.mp4
 0x040|                        01 00                  |        ..      |        count: 1 0x48-0x4a (2)
      |                                               |                |        records[0:1]: 0x4a-0x47e (1076)
      |                                               |                |          [0]{}: record 0x4a-0x47e (1076)
-0x040|                              01 00            |          ..    |            type: "Rights management header" (1) 0x4a-0x4c (2)
+0x040|                              01 00            |          ..    |            type: "rights_management_header" (1) 0x4a-0x4c (2)
 0x040|                                    30 04      |            0.  |            len: 1072 0x4c-0x4e (2)
 0x040|                                          3c 00|              <.|            xml: "<WRMHEADER xmlns=\"http://schemas.microsoft.com/..." 0x4e-0x47e (1072)
 0x050|57 00 52 00 4d 00 48 00 45 00 41 00 44 00 45 00|W.R.M.H.E.A.D.E.|