Topping A90 failure issues. Should I try a 3rd A90?

After 2 abrupt failures it would seem like it's time to move on to something else. Why risk another disappointment with Topping

External power supply? Did you replace the power supply when you replaced the 1st one.?

This seems strange as I’ve not heard of Topping having major problems like this, but I guess the A90 is a newer model so who knows?  I am wondering, though, if there may be something in your setup that could be causing this as it is a bit peculiar.

I vote no.

So you are that kid who kept burning his hand on the stove.

My book is one and you’re done!

MOVE ON!!

@dreas  We have a new D90 (non-MQA) that had some odd distortion issues when we got it. We were running it from the USB port of our shop Mac Powerbook. Apparently the settings got scrambled and we had to reset what was being sent to the USB port. This cleared up the bursts of static and outright distortion. You might take a look and see if this is what is going on. We've not had a lick of trouble with it since.

Thanks, sincerely, for everyone's comments.
@atmasphere long story short, I've diagnosed 2 different laptops. I did have a static issue with a new Dell (I think it's their UBS audio -- part of the motherboard -- that's frankly cheap) but an 7 year old Lenovo X1 Carbon works great. I tried 3 different A-B USB cables and 2 of ifi inline jitter devices. No help. But this is different. After a loud static discharge, one channel went out. The volume knob - turning it down or up -- made it worse. I'm 90% sure it's the Topping A90 has a problem. As to an eariler comment from @ audio2design there is no external power supply on these. The A90 & D90 have their own. (Earlier Topping models did have an external power supply). Again, thanks to all. I loved the idea of this set but I think there's a build issue? Who knows. 

@soix valid point but I'm not sure what could contribute to it from my setup. I use it as a standalone setup, the Topping A90 & D90 with the recommended XLR balanced cables. The only inputs are a USB A-B connection to the D90 (DAC, not amp) and power cords into a separate power conditioner/strip.  

Have you used the same balanced cables on both units?

@djones yes. I purchased them from Apos as part of their bundle with the A90 & D90.

But this is different. After a loud static discharge, one channel went out.

Sounds a bit like an opamp failure. And really bad luck, considering how well the unit measures.

 Very strange.  If there weren’t viable competitors I’d consider trying a third A90, but there certainly are and it seems for whatever reason the Topping’s not working in your system.  If it’s me, at this point I’d shell out an extra $100 and try the Singxer SA-1, which may actually be an even better amp.  Just my $0.02, and best of luck whatever you decide. 

You might try posting a question on ASR. John Yang is the user you would want to contact I believe he works for Topping. I know there are a couple of threads where some problems with the A90 are discussed one thing he mentioned was a bad XLR cable can be a cause. 

@djones51 Thanks very much! 

I have the A90 and it is a workhorse for me. I have been using it recently to break-in new gear. So that means playing it 24 x 7 for a week (no problems). In this scenario I use iPhone ear plugs to output sound. 

When it is not doing break-in work I enjoy the A90 with a Matrix Mini-i 3 Pro DAC using some very old Audience AU24 XLR interconnects. I bought the Mini over the Topping D90 because it was reviewed to be a bit better and also for the incredible ROON streaming options with the Matrix (so no direct computer connection).

I listen to this combo with Meze Empy headphones and it is amazing for the price. This combo comes close to the quality of my Benchmark HPA4 + DAC3B pairing but that combo is much more money.

I know this chain is a bit old, but I think the same thing just started happening with my A90. Static in the right channel from all headphone outs (both balanced outs and single ended out). It seems to be certain frequencies or volume levels that are effected (e.g., I'll head the same "static" noise on each drum hit).

Tried different headphones, different cables, different outputs from the computer (USB and optical to the D90, then XLR to the A90). The RCA outs on the A90 to my speakers do not have the same issue.

@audioville I ended up getting a 3rd A90 (after considering other amps) and so far, so good. Depending on where / when you purchased the A 90, you may still have a warranty (I think it is a 1 or 2 year warranty?). I purchased the Topping "ensemble" D90 MQA & A90 from Apos. They were very slow to respond but they eventually replaced both failed units. (They don’t reveal if their online support is in China or stateside, or if stateside has to get approval from the China manufacturer so it’s odd. Their email support comes in flurries at odd times suggesting they're based overseas; it is messy and disorganized.)

I’d also check if you are using an aftermarket (Hart, Periapt, or other) balanced interconnect and/or headphone cable whether or not it "shorted" and caused the problem. This is hard to diagnose and hard to find an engineer on forums who might explain if this could even cause the issue. At some point, you stop wasting time on what happened and just replace the cables & get a new A90 and get back to music. :-) I very well may be wrong, but I am suspicious if a cable could cause a short or damage to the amp.

I hope you are able to get it replaced. When it works, I love the A90 & D90!

My first a90 got the same exact problems. I don’t use it as much, but after a few months or maybe even a year, it blew up. One of the channel, got statics problems just as described. Still within warranty, returned and exchanged for a second one. Did not used the second a90 until 3 months later. Right out of the box, power light blink red, after turned off but not right away. Than later, discover another problem. When used in high gain, music will blackout in spit second, kind of like a skip pause every 3 mins. Sometimes less sometimes more…Returned and just received my third a90. It is still in testing period. Not sure how long this will last…
I lost confident with Topping…😩

dreas
Topping A90 failure issues. Should I try a 3rd A90?

Wow! they get raved about over at Audio Science Review and get second from the top honors. I’d try a third, could have just been a bad batch of one component.
https://www.audiosciencereview.com/forum/index.php?threads/topping-a90-headphone-amplifier-review.13...

Cheers George

UPDATE, thanks all for comments. I did in fact receive a 3rd Topping A 90 and it has been working so far. 

Enjoy the music!

The Topping DACs are excellent bargains in high end audio and good examples of how high end audio is not about price but intention.

I am now using a Topping pre90 preamp and I am amazed how good it sounds. It does not have any features other than inputs and volume. However, the sound is extremely clean with nothing added. Cost is $599.

My other preamp is the CODA 07x which cost a lot more and adds warmth to the sound. 

I am very impressed by Topping.