Lapses in fpv after dji go 4.1.10 update
1136 6 2017-10-11
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bighi
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Flight distance : 47455053 ft
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Austria
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I updated yesterday and have been having lapses in fpv ever since. So far I have tried everything with no success. Deleted and reinstalled the app three times. The only thing left to do is to swap the cable. Though it would be one heck of a coincidence to have my cable go bad right after the update. The lapses are bad enough to make my mavic unflyable in fpv. This is something I've never experienced in the mavic since launch. If you folks have any solutions I'll gladly take them.
2017-10-11
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DJI Thor
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Flight distance : 13602 ft
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Just to verify, you mean that you can't get the image transmission on your app, right? Please check the following steps:
1. Please check could you control the gimbal by RC? If the gimbal doesn't move, please try to relink the drone and RC.
2. If you can control it, could you please tell us what mobile device are you using? And please try to replug the connecting cable between the RC and the device. You can also try to use your original device cable for connecting, plug it in the bottom port, don't forget to unplug the left cable first.
3. Upgrade the firmware of the RC if it is needed.
If the case persists, please try to test in another device.
Please keep us updated if the problem persists, thank you.
2017-10-11
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bighi
lvl.4
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Spain
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Fpv comes on. That is not the issue. The issue are skips in fpv transmission. Sometimes seconds missing even at close range. There was never an issue since November of 2016 on this mavic. The issue began just after the update of dji go to 4.1.10
2017-10-11
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Nazar78
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Flight distance : 5106037 ft
Singapore
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Hello,

Which device are you using? The DJI GO 4 is a power hunger app to each update. Here's the two common lags that I noticed:

1. FPV lapses like you mentioned, sometimes up to 30secs+ during recording.

2. Command lag e.g. try to toggle the gimbal quickly up and down during recording with the 5D button when you noticed the FPV lapses. You will notice the physical gimbal movement is not immediate, adding more lags to the FPV.

I've tested on several device and I have come to a conclusion that heat from the handheld device running this app is causing all these lags. Once overheating, the device will start throttling the CPU/GPU frequencies including auto turning off CPU cores depending on your device thermal protection. It sometimes kicks in even if the device is still not too hot. Until the app codings has been properly optimized, the only way I can prevent this is to tweak my device but unfortunately this requires root. If you are able to root your device do continue reading else I'm sorry I can't be much help.

Here's what I did for my few years old Samsung Note 3 with stock 5.0 ROM but custom kernel. Any custom kernel should work if they provide the support and you can edit using any kernel editor or init.d run-parts shell scripts which most custom kernel supports.

1. Set the internal I/O scheduler to NOOP. Readahead cache buffer to no larger than 512KB, high values will introduce more latency. Same goes to the external sdcard if you have set the DJI GO 4 app to cache it there. This helps with the FPV and video cache as it reduces CPU utilization.

2. Less voltage = less heat. Tune down the voltage for all frequencies -5mV each step then stress with any benchmark app in between until you get a stable sweet spot, no overclocking, had mine -50mV all across. This requires custom kernel.

3. Increased the frequency thermal protection temperature limit till about 90-95°C and importantly ensure it doesn't auto turn off any CPU cores. This requires custom kernel.

With the above tweaks I still get thermal throttling but at a minimal level so the frequency especially for CPU doesn't dip down too low often. I've flown few times with the latest 4.1.10 in max screen brightness on a 33°C sunny day and so far no lags whatsoever.

2017-10-11
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bighi
lvl.4
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Spain
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There was no extra heat from my device. I wasn't recording. I was just flying and it was pretty darn impossible to fly. But I found the solution. I backdated to dji go 4 4.1.9 and it works perfectly. I want no business with 4.1.10. Forget it.
2017-10-11
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DJI Diana
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Flight distance : 2408 ft

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bighi Posted at 2017-10-11 11:54
There was no extra heat from my device. I wasn't recording. I was just flying and it was pretty darn impossible to fly. But I found the solution. I backdated to dji go 4 4.1.9 and it works perfectly. I want no business with 4.1.10. Forget it.

What mobile device are you using?  Anyway, glad to hear that you've found a solution.
2017-10-12
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bighi
lvl.4
Flight distance : 47455053 ft
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Spain
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To be honest, the mobile device used has far less relevance when one has used it successfully for just about a year. Then low and behold, app is updated and the fpv goes to hell.
2017-10-12
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