Qt: Don't crash if audio feed is null.
Qt: Don't crash if audio feed is null.

hrydgard/native,libretro/ppsspp-native,unknownbrackets/native,hrydgard/native,hrydgard/native,zhykzhykzhyk/ppsspp-native,unknownbrackets/native,libretro/ppsspp-native,libretro/ppsspp-native,unknownbrackets/native,zhykzhykzhyk/ppsspp-native,hrydgard/native,zhykzhykzhyk/ppsspp-native,zhykzhykzhyk/ppsspp-native,libretro/ppsspp-native,unknownbrackets/native