[Greeni]

Based on your description I really have no idea what the cause of failure might be. With sound that intermittently comes and goes, my first guess would be a broken solder joint somewhere. Are you able to measure if there's any sort of offset on the channels? 

I can certainly ask the techican who do the repair work to check again.

Meanwhile, just in case it is beyond repair, I would like to know what other headamps other KICAS users have upgraded to.

 

[Armaegis]

What sort of price range are you looking at? Do you want bass control like the Caliente?

 

[Greeni]

What sort of price range are you looking at? Do you want bass control like the Caliente

Hope to keep the cost below $700, bass enhancement / control not necessary.

 

[Armaegis]

The amp that I had for the longest period of time is the Bottlehead Crack + Speedball. This requires a bit of DIY on your end though. I've always been quite impressed with the Bottlehead gear if you like building your own (and they just released a new amp too, though it's a bit above your budget)
 
At the moment I'm quite happy with the Nuforce HDP and Centrance DacMini. Both perform very well as amps, though you're paying for the dac functionality in there as well. Schiit makes some pretty good gear for the price as well. 

 

[wyki]

I haven't used it but when I was buying the KICAS, an alternative that I considered is the Audio GD C2C amp.  http://www.head-fi.org/t/383033/review-audio-gd-c2c-headphone-amp-vs-little-dot-mkv