flv from vlc to ffmpeg live video error when no sound temporarily

Question

Hi

When we get live stream from vlc to ffmpeg , wherever there is sometimes 5-6 second no sound part of video , then ffmpeg is dead with this log

flv @ 0x8b426d0]illegal ac vlc code at 4x6

[flv @ 0x8b426d0]Error at MB: 142

[flv @ 0x8b426d0]concealing 257 DC, 257 AC, 257 MV errors

[mpegts @ 0x8b44e50]dts < pcr, TS is invalid

Is there anyway to avoid this problem ?