www.e-stim.net

I'm seeing a serious lack of responsiveness on the knobs for the A & B channels in stereo and adv stereo modes even with no audio being played. So here, I'm trying to set power levels to, say, 30% before starting the audio.

The knobs are fine in all other modes. I've tried full reset several times, taken the battery out, done a full reset with just the mains in. Still it seems to persist. I did notice that when the 2B powers on, channel A has a green light lit on the right hand side of the box even when both power levels are set to zero. Is that normal and I've not noticed?

If all else fails, I might try reloading the firmware.

Has anyone else seen anything like this? I'm sure I've seen similar post, but they relate to responsiveness when the audio is actually playing.

Thanks.

Is it the same if you unplug the audio input cable to the 2B? I only ask because at one stage I was using an old mobile phone as a sound source that produced a constant low hum until I started playing an audio track.

Just because you are not playing audio, the 2B is still trying to convert the input signal to a usable output. And mobiles are never great for playing audio

Si

mrbutt89 wrote: ↑Thu May 20, 2021 9:30 am Is it the same if you unplug the audio input cable to the 2B? I only ask because at one stage I was using an old mobile phone as a sound source that produced a constant low hum until I started playing an audio track.

Yes, I tried disconnecting everything for exactly that reason. The green light on the 2B coming on after power-up is not something I remember though. I thought both A and B channel lights should be out when it starts and is at zero power.

There is no green light on a 2B.... you probably find you are seeing reflections or bleed from the backlight.

Si


Sent from my iPhone using Tapatalk

OK. I know the A and B channel lights show blue when they're on, so may be I'm seeing that at an angle. Odd that it was only the A channel light though. Anyway, I've checked the responsiveness again with absolutely no cables connected and it seems fine. Maybe I only disconnected the audio cable at the machine end and the cable itself was generating some noise. Anyway, put it down to some Heisenberg-eque problem...

mrbutt89 wrote: ↑Thu May 20, 2021 9:30 am Is it the same if you unplug the audio input cable to the 2B? I only ask because at one stage I was using an old mobile phone as a sound source that produced a constant low hum until I started playing an audio track.

Actually, that sort of makes sense. This is the same old Mac that I had problems with the USB port. Maybe all the ports have noise on them, it just isn't detected (or is corrected) in other circumstances. Anyway, it's a good theory.

tdg wrote: ↑Thu May 20, 2021 1:18 pm Odd that it was only the A channel light though.

I think there is maybe an internal LED that causes the 'green light' illusion on channel A. It used to confuse the fuck out of me but it's quite normal.

tdg wrote:OK. I know the A and B channel lights show blue when they're on, so may be I'm seeing that at an angle. Odd that it was only the A channel light though. Anyway, I've checked the responsiveness again with absolutely no cables connected and it seems fine. Maybe I only disconnected the audio cable at the machine end and the cable itself was generating some noise. Anyway, put it down to some Heisenberg-eque problem...

It’s because the led for the backlight on the lcd bleeds through the channel A led.

Si


Sent from my iPhone using Tapatalk

estim_si wrote: ↑Thu May 20, 2021 6:59 pm

tdg wrote:OK. I know the A and B channel lights show blue when they're on, so may be I'm seeing that at an angle. Odd that it was only the A channel light though. Anyway, I've checked the responsiveness again with absolutely no cables connected and it seems fine. Maybe I only disconnected the audio cable at the machine end and the cable itself was generating some noise. Anyway, put it down to some Heisenberg-eque problem...

It’s because the led for the backlight on the lcd bleeds through the channel A led.

Si


Sent from my iPhone using Tapatalk

Indeed, and I think it only presents itself at certain angles, which is why I only noticed it this time.