blade 7000s no sound

Try taking your hd lead out and re-bed it both on your box and tv i had this problem before, replacing the lead solved it

Quote from pipiai

i guys, no sound in some channels
any ideias ?

I had the same problem with the blade 8000s. I solved it by going into settings and changeing Dolby hdmi to Dolby spdif in the a/v output settings

Try a rescan some channels change frequency and can cause the audio to go.