It's been 2 flights I found that when I command the FO to change altitude, the MCP Alt would go up to either 50000 or 00000 and I couldn't do anything to change it no matter what I did; scroll manually nor command the FO. I followed the troubleshooting instruction in the manual, so I turned off the "voice" toggle and turned it on again, and it worked (now the alt indicator in the MCP was changeable).But then another issue occured, I couldn't hear the FO response to my departure brief, I repeated the command over and over and they were written in the green box as I presume I said it correctly. I also tried to turn on and off the HS button, no avail. I also tried other commands such as changing speed and heading so that the FO would read back the instrustions.I ended the flight, and went to the gate, everything is back to normal when I performed before start checklist. Your help would be greatly appreciatedKind regards.

Hi,I answered this in the FSX forum.Cheers,