Audioboxer
New Head-Fier
Hi everyone,
This is my last ditch attempt to get some advice on using the USB functionality of this DAC before I just decide to give in and use optical.
A short chain kicked off in the dedicated topic looking for help but given low traffic in there I'd like to open up to all of you https://www.head-fi.org/threads/fostex-hp-a4bl-the-a4-with-balanced-output.792916/post-16330636
The tldr is I have a piercing pop noise coming out of one of my speakers when using USB most noticeable when sound is first sent to the speakers/power on, but reproducible if I have no audio playing and then start something up like a YouTube video. When the audio is playing there is no issues, but if I use the seek bar on YouTube, that brief gap of silence before audio starts again produces that piercing pop. If I swap the phono outputs on the back of the Fostex to reverse R/L, the pop goes to the other speaker.
From the topic above I've tried a USB powered hub, a laptop on battery, another USB cable with ferrites (instead of Fostex default), 2 sets of powered speakers, an AV loop isolator and just today Fostex sent me a grounded power supply. Nothing has helped. The AV isolator loop actually INTRODUCED hum/buzz, neither of which I have at the moment lol, just the pop. Though it was a cheaper Amazon phono AV loop isolator (quality might be an issue here). Optical works absolutely fine, with either set of speakers.
The only common denominator between my laptop and PC is Windows 10. I have also tried to get audio playing through a Galaxy S20, but for whatever reason whilst my S20 seems to pickup the Fostex, I can't get it passing any audio over USB.
Has anyone had an issue like this? (I'll try record noise later for you). I do know the easy answer is use optical, just forget USB. But it's hard to give up troubleshooting
I know there are more expensive USB isolators that I guess might produce a result than an external powered USB hub. £50 a pop though for one of those iFi iSilencer dongles and a lot of people seem to use them for hum/buzz, neither of which I think I have. Mines is more like a sharp pop, it's not constant.
Cheers
This is my last ditch attempt to get some advice on using the USB functionality of this DAC before I just decide to give in and use optical.
A short chain kicked off in the dedicated topic looking for help but given low traffic in there I'd like to open up to all of you https://www.head-fi.org/threads/fostex-hp-a4bl-the-a4-with-balanced-output.792916/post-16330636
The tldr is I have a piercing pop noise coming out of one of my speakers when using USB most noticeable when sound is first sent to the speakers/power on, but reproducible if I have no audio playing and then start something up like a YouTube video. When the audio is playing there is no issues, but if I use the seek bar on YouTube, that brief gap of silence before audio starts again produces that piercing pop. If I swap the phono outputs on the back of the Fostex to reverse R/L, the pop goes to the other speaker.
From the topic above I've tried a USB powered hub, a laptop on battery, another USB cable with ferrites (instead of Fostex default), 2 sets of powered speakers, an AV loop isolator and just today Fostex sent me a grounded power supply. Nothing has helped. The AV isolator loop actually INTRODUCED hum/buzz, neither of which I have at the moment lol, just the pop. Though it was a cheaper Amazon phono AV loop isolator (quality might be an issue here). Optical works absolutely fine, with either set of speakers.
The only common denominator between my laptop and PC is Windows 10. I have also tried to get audio playing through a Galaxy S20, but for whatever reason whilst my S20 seems to pickup the Fostex, I can't get it passing any audio over USB.
Has anyone had an issue like this? (I'll try record noise later for you). I do know the easy answer is use optical, just forget USB. But it's hard to give up troubleshooting
I know there are more expensive USB isolators that I guess might produce a result than an external powered USB hub. £50 a pop though for one of those iFi iSilencer dongles and a lot of people seem to use them for hum/buzz, neither of which I think I have. Mines is more like a sharp pop, it's not constant.Cheers
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