Loud crack in the left channel - tube issue?


Hi -

We use a HAG-USB, a Musical Fidelity Trivista DAC and Musical Fidelity A308. This afternoon, my wife stated she had heard several loud cracks from the left channel. Then I heard a loud thump too and turned everything off. An hour later, I turn things back on and the left channel is dead. Turn them off again plug in an Ipod to determine if it is an amp or DAC issue - now everything is back to normal. Any suggestions as to what is going on? I was under the impression the small tubes in the MF DAC were bomb-proof?

Cheers,
Soren
mogelsvs
I am the second owner of the dac, so I can't say how many hours it has on it. I guess I will have to find somewhere to get the tubes replaced here in the DC area.

Cheers,
Soren
Probably issue with the tubes which has happened in my system.

How old is the DAC?