Left it for a good while to warm up
353892
UPDATE

So given the other positive reviews on this Amp I decided to try and figure out the issue. I had assumed it was a bad tube but it turned out that was not the case. The actual issue was that it seems not to like what my iMacPro and Macbook Air USB 3.0 interface. The former is running mavericks and the latter is Yosemite. The sound is horrible using those sources, there is a lot of distortion, and spurious noise. The set is simply USB from device to amp and amp connected to my DT 800 (600 Ohm) headphones. I connected a PC running windows 8 and it was like day and night. The sound was as the other reviewers claim. I tried running it off my Imac pro via a USB 2.0 hub and the sound was much better but still full of pops. Going to try a powered hub to see if that sorts things out.

However much as I loved the sound when I used the PC I'm still going to have to say buyer beware due to this apparent issue when using certain sources, so still buyer beware.... If anyone knows of a fix let me know.

ORIGINAL REVIEW
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Looks lovely sounds awful, set up the amp plugged into a USB source. Left it for a good while to warm up. Tried it out, the gain is terrible, one click will send it clipping. On music with a lot of dynamic range it simply loses part of the range, turn up the gain just makes it clip. No external means to adjust anything. Save your money..not worth it
4829429
I loved it for about a week, then the motor commenced heating up and making noise, then the noise vanished but the motor heating is on and off. I haven't called the company as of yet because it's still working, and I purchased protection plan from Amazon. I haven't used it for 3 days now, thinking to give the motor a break. Not sure what to do though. I was thinking of return it and get a different brand. Will provide update later.
1903
I wish it would've warned me not to leave it on my hardwood after turning it off.  Nice heat mark was left...
2172112
At times a little skippy.  Let it warm up per instructions.
570545
Temp dropped to 10 degrees and I had to remove some clothing 'very warm'.
3368257
Hi, Thank you to the suppliers for packing it well. And quick shipment.  I forgot when but it arrived, but well before the estimated arrival date. The cord that connected from the heat elemant to the car outlet, got a bit warm. if i left it in the outlet too long about 6 minutes, before i needed to unplug. I don't know if a higher guage wire might help carry the electrons better or more insulation might help solve the wire heat issue.  I just don't know . I have not used it much, But for the 2 times I have tried to use it, heat element, heated water enough for my like . Nice product.
538175
It definitely gets hot if you leave it too long. Good thing I tested instead of leaving it overnight
1954320
I COULD LEAVE IT FOR DAYS AND THEN COME BACK TO IT.  WHEN I DID COME BACK TO IT, I DID FIND IT INTERESTING
3263031
Overheated when dad used it. Had to let it cool for awhile before we could use it again. Bought it for dad.
2712767
Maybe if you ran it under hot water for 30 seconds you could call it warm. Or just hold it in your arm pit for 5 minutes...that should do it!  But it's just a thick, blunt painted chunk of metal with some squigglies along one edge. Nothing revolutionary here.
2254373
after leaving the cord plugged in for a while you have to unplug and replug. hardly an inconvenience, but worth a mention
3733787
Have not had a chance to use for an extended period of time. Will revisit post in the near future.
1031493
It was a nice watch for the price, but I guess it was not "sealed" so good since it could not handle cold weather and the condensation coming from when you go indoors after being outside in minus degrees. It took almost a week for the tiny condensation water drops to dry out, but the black clock-face material (paper?) now has some bubbles in it so I guess the quality of the watch was not so good after all. But at least it was a nice watch for a few hours ;)
126946
I left on warm and the the chocolate got hard and i was not able to melt the chocolate that was already flooting threw the machine once its floating do not turn it off it will not warm it melt it again
3440035
Took a while to expand. Give this a little while to expand properly. Since it's somewhat cold in the area, I put ours next to a heater for a little while until it expanded completely.
Smelled a little; but that slowly went away.
4968154
Took our cat a little while to warm up to this weird thing on the wall but now he likes it :)
3521739
Like the compression feeling, what I don't like is that when using cold it doesnt stay cold that long. After about ten minutes it is pretty much room temp, this after it has been stored in a freezer.