diff --git a/src/apps/common/dng_writer.cpp b/src/apps/common/dng_writer.cpp
index c945edce7..82bc065a5 100644
--- a/src/apps/common/dng_writer.cpp
+++ b/src/apps/common/dng_writer.cpp
@@ -248,6 +248,7 @@ void thumbScanlineIPU3([[maybe_unused]] const FormatInfo &info, void *output,
 
 		uint16_t val1, val2, val3, val4;
 		switch (pixelInBlock % 4) {
+		default:
 		case 0:
 			val1 = (in[1] & 0x03) << 14 | (in[0] & 0xff) << 6;
 			val2 = (in[2] & 0x0f) << 12 | (in[1] & 0xfc) << 4;