If the update of program is aviable, after updating a virus database or when detects any virus, Avast shows an appropriate visual notification (above the system tray) and plays a sound signal (one or three beeps an then a woman voice). In XP it works correctly, but in ReactOS is not. There is a fully silence, no any notifications. When I captured debug log, for example I placed the WannaCry virus in random directory and rename file extension from .EXE to .exe, although in XP it's detected immediately, without renaming. Antivirus detects and deletes a file correctly, but doesn't notify about it. In antivirus settings visual and audio notifications was already enabled.
UPD: If to terminate explorer.exe, the notifications shows correctly, but sounds still doesn't play. See screenshot.