# Synth - audio drops out in what sounds like bit rate distortion **URL:** \ **Category:** Archive\ **Tags:** synth, needs-info\ **Created:** [December 2, 2024, 12:19am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535 "2024-12-02T00:19:41Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 2, 2024, 12:19am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/1 "2024-12-02T00:19:41Z")
### Bug Description On most sounds, I’ll be holding a sound out and there’s a slow fade to distortion that is very similar to dialling in bit rate reduction (down to 2 or 4 bit) then fades back in. There seems to be no pattern to it, no CPU warning, and difficult to reproduce (rather random) ### Steps to Reproduce 1. \_load in a scene (I used Atcha\_Samadhi) 2. …latch any key on the “resonant lift” (blue) patch 3. … wait about 5 secs or up to a minute ### Occurrence / Frequency Sometimes ### Found in Firmware - **Version** : _1.01_ - **Build** : _1459_ ### Attachments wasn’t allowed to put in a clip example ---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 2, 2024, 1:06am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/2 "2024-12-02T01:06:26Z")
It’s the PHZ synth that keeps doing that to me. ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 2, 2024, 11:56am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/3 "2024-12-02T11:56:43Z")
Hey @charlesreeves, i’ve updated your user status. See if you can upload an audio sample now. Because i’m not sure i know exactly what i’m supposed to listen for - it sounded clean to me. ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 2, 2024, 11:37pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/5 "2024-12-02T23:37:25Z")
---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 2, 2024, 11:38pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/6 "2024-12-02T23:38:56Z")
Yes that is exactly what is going on with me too. I bet it’s the PHZ engine! I made a report here today [Polyend Synth PHZ farting out - #4 by mokujin\_music](https://backstage.polyend.com/t/polyend-synth-phz-farting-out/16566/4) ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 3, 2024, 8:36pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/7 "2024-12-03T20:36:20Z")
Closed the above report by @BROCKSTAR for duplication, but leaving a link here for future reference: > [@Polyend Synth PHZ farting out](https://backstage.polyend.com/t/polyend-synth-phz-farting-out/16566): > > Bug Description The PHZ synth really needs looked at bad. There’s something going on with the volume of it. It seems if you have it higher than -20db on main mixer volume, it starts distorting / crackling into low bit rate distortion and cutting in and out especially with the mix control high in the synth engine oscillator section too and the volume high in the 3rd page of the oscillator section. I have seen a few others here mentioning the same type of thing going on and I bet it’s due to PHZ … ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 3, 2024, 8:37pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/8 "2024-12-03T20:37:10Z")
It does seem like it’s a combination of things that causes this “effect” ? If you lower the levels of the PHZ engine, does the noise/weirdness still occur? ---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 3, 2024, 10:14pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/9 "2024-12-03T22:14:08Z")
it helps it when it’s lower as written in my statement, but it shouldn’t be doing that though no matter the volume? Which makes me believe it’s more of a volume thing more then anything. ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 3, 2024, 10:15pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/10 "2024-12-03T22:15:46Z")
Yeah that’s what i’m thinking as well, just trying to confirm this. Because then it’s most likely not a synth engine issue, but more like an overall headroom issue. ---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 3, 2024, 10:24pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/11 "2024-12-03T22:24:29Z")
I thought so too but if it was that wouldn’t it do that with all the engines? It only seems to do it with this one. ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 3, 2024, 10:34pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/12 "2024-12-03T22:34:44Z")
I mean you could test it. Drive the volume of the other engines past 100% (not just in the mixer, but the individual voice as well) and see what happens. ---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 3, 2024, 11:06pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/13 "2024-12-03T23:06:54Z")
I have to some extent and they don’t do what PHZ is doing. ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 5, 2024, 8:33pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/14 "2024-12-05T20:33:44Z")
I’ve tried changing levels, unsyncing delays, etc. I can’t control when it happens, but I’ve had this happen with all of the engines, at various levels, in various “sync” states. The problem doesn’t seem to be, nor does it sound like, any kind of audio-level distortion or overdrive, hence I keep referring to it sounding more like bit rate reduction (note: I can reproduce the exact same sound by using Ableton’s Redux plugin whilst reducing bit rate below 8bit). I understand headroom issues with the unit (many of the Scenes in the default set actually overload, which is another strangeness about the unit out-of-the-box) and since this sort of work is my profession for the last 20 years, I’m confident the sound is nothing like an audio overload distortion. No squaring of wave peaks. I’ve recorded some of it into audio to see the wave shapes and what it’s doing is actually dropping to digital zero in between waveforms; something that happens in the bit realm. I can provide examples if you like. ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 5, 2024, 8:43pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/15 "2024-12-05T20:43:02Z")
I should add: I really want to solve this because I love the workflow of the Synth and the sound of it. I just want this to be solved with a firmware update or maybe I have a defective unit? Looking to solve this mystery ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 5, 2024, 8:43pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/16 "2024-12-05T20:43:59Z")
![Screenshot 2024-12-05 at 15.40.16](https://backstage.polyend.com/uploads/default/original/2X/a/abd2b2ca220c19ee48e1b03f08aecbcf83b77ced.png) ---
**Author:** ![Sandroid](https://backstage.polyend.com/user_avatar/backstage.polyend.com/sandroid/32/172_2.png) [@Sandroid](https://backstage.polyend.com/u/Sandroid)\ **Post date:** [December 6, 2024, 1:20pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/17 "2024-12-06T13:20:10Z")
Hey @charlesreeves thank you so much for all the details. Btw, just to be clear, i’m not being dismissive at all, just trying to create a simple reproducable case here to simplify bug fixing for the dev team 😊 ---
**Author:** ![BROCKSTAR](https://backstage.polyend.com/user_avatar/backstage.polyend.com/brockstar/32/4220_2.png) [@BROCKSTAR](https://backstage.polyend.com/u/BROCKSTAR)\ **Post date:** [December 7, 2024, 11:59am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/18 "2024-12-07T11:59:26Z")
i think i figured out the issue with PHZ. The shape 1 parameter. When it’s 0 to 20 or somewhere in that range, it starts acting up. However there’s something with the mix parameter too, if it’s too high in that engine it still causes issues. Negative values on the mix parameter works better. Sometimes it’s hit or miss, so the above may not help after-all. Still think this engine needs to be looked at badly! ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 9, 2024, 3:01am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/19 "2024-12-09T03:01:21Z")
Agreed about the engine needing to be looked at. I think the CPU is strangely underpowered considering what the unit is supposed to be capable of. Granted, $500 is pretty cheap comparatively to other synths, but I feel like my OP-Z has more power to it. ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 9, 2024, 3:10am UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/20 "2024-12-09T03:10:58Z")
I made a comment on a related post that could be pointing the same direction for this issue: “I’m going to sound nuts here: my thinking is this might be an SEU (single event upset). In microprocessors with limited data throughput pathways, this can easily be an issue. More modern electronics have multiple throughput pathways making SEUs less troublesome. I hope that’s not the case with the Synth because that would mean it’s not resolvable with a firmware or software update.” ---
**Author:** ![charlesreeves](https://backstage.polyend.com/user_avatar/backstage.polyend.com/charlesreeves/32/4308_2.png) [@charlesreeves](https://backstage.polyend.com/u/charlesreeves)\ **Post date:** [December 14, 2024, 7:20pm UTC](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535/21 "2024-12-14T19:20:57Z")
I went for a couple of days of sporadically using the Synth in session and it worked okay. Then, a couple of days following, and today, on the same patches and under the same circumstances, it’s dropping out / glitching to the point of making my clients rather frustrated. I’m within my return window and, I’m sad to say, I’m probably going to get an RMA and send it back. I love many things about this unit, but its unreliability and no solution anywhere that I can find is a deal-breaker for me. [Next page](https://backstage.polyend.com/t/synth-audio-drops-out-in-what-sounds-like-bit-rate-distortion/16535.md?page=2)