# LimeSDR : Runtime warning in FFT view

**URL:** <https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289>\
**Category:** LimeSDR\
**Created:** [25 July 2026 11:11 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289 "2026-07-25T11:11:11Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![zvivered](https://avatars.discourse-cdn.com/v4/letter/z/58f4c7/32.png) [@zvivered](https://discourse.myriadrf.org/u/zvivered)\
**Post date:** [25 July 2026 11:11 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/1 "2026-07-25T11:11:11Z")

</div>

Hello,

I’m using the GUI with the following parameters:

Sample freq. = 18.285714[MHz]

Band width = 12[MHz]

Center freq. = 530[MHz]

Over sample = 2

RX Gain = 30[dB]

Rx Path= 3

Upon START in the fftviewer I’m gettin the following errors:

```auto
[14:06:26] WARNING: USB ep:83 Rx0: 22.360 MB/s | TS:621722640 pkt:192075 o:0(+0) l:189446(+5459) dma:192075/192091(+16) swFIFO:0[14:06:27] 
WARNING: USB ep:83 Rx0: 22.491 MB/s | TS:640013280 pkt:197566 o:0(+0) l:194936(+5490) dma:197566/197582(+16) swFIFO:0[14:06:28] 
WARNING: USB ep:83 Rx0: 22.561 MB/s | TS:658276720 pkt:203074 o:0(+0) l:200441(+5505) dma:203074/203090(+16) swFIFO:0[14:06:29] 
WARNING: USB ep:83 Rx0: 22.692 MB/s | TS:676580960 pkt:208614 o:0(+0) l:205979(+5538) dma:208614/208630(+16) swFIFO:0[14:06:30] 
WARNING: USB ep:83 Rx0: 22.675 MB/s | TS:694863440 pkt:214150 o:0(+0) l:211511(+5532) dma:214150/214166(+16) swFIFO:0[14:06:31] 
WARNING: USB ep:83 Rx0: 21.262 MB/s | TS:713147280 pkt:219341 o:0(+0) l:216702(+5191) dma:219341/219357(+16) swFIFO:0

```

According to ‘Gemini’ it means data loss. When I tried sample rate of 1[MHz] I did not get any warninig message. The SDR is connected to a USB3 (blue connector).

Does it make sense ?

Thank you,

Zvi

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<div class="post-metadata">

**Author:** ![ricardas](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/ricardas/32/86_2.png) [@ricardas](https://discourse.myriadrf.org/u/ricardas)\
**Post date:** [26 July 2026 09:11 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/2 "2026-07-26T09:11:19Z")

</div>

> [@zvivered](#):
>
> The SDR is connected to a USB3 (blue connector).

I assume you’re using LimeSDR Mini. Sometimes if there were any issues during device plug in to the USB port, it could be enumerated as a USB 2.0 device. That would limit the data rate to half duplex max 40MB/s. I suspect that is the case you’re seeing here, try to unplug the device, and reinsert into the port again. Verify that the devices gets enumerated as USB 3.0.

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<div class="post-metadata">

**Author:** ![zvivered](https://avatars.discourse-cdn.com/v4/letter/z/58f4c7/32.png) [@zvivered](https://discourse.myriadrf.org/u/zvivered)\
**Post date:** [26 July 2026 09:54 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/3 "2026-07-26T09:54:03Z")

</div>

Hi,

I double checked that the Lime is enumerated as USB 3.1

But if the sample rate \> 10MHz, there are many losses.

Is it connected directly to the PC or with a 50cm USB3 cable.

The USB3 rate is very high compared to the stream rate.

Thank you,

Zvi

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<div class="post-metadata">

**Author:** ![zvivered](https://avatars.discourse-cdn.com/v4/letter/z/58f4c7/32.png) [@zvivered](https://discourse.myriadrf.org/u/zvivered)\
**Post date:** [3 August 2026 02:26 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/4 "2026-08-03T02:26:22Z")

</div>

Hello,

Can you please explain the losses we are getting ?

Can I measure the USB 3.x input rate to my PC in another way in order to prove that the rate it OK ?

Can the Mini keep the samples in its internal memory and I will read them upon stream stop ?

Is there a paid support plan for this product ?

Thank you,

Zvi

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<div class="post-metadata">

**Author:** ![ricardas](https://yyz2.discourse-cdn.com/flex034/user_avatar/discourse.myriadrf.org/ricardas/32/86_2.png) [@ricardas](https://discourse.myriadrf.org/u/ricardas)\
**Post date:** [14 August 2026 12:02 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/5 "2026-08-14T12:02:27Z")

</div>

> [@zvivered](#):
>
> Can the Mini keep the samples in its internal memory and I will read them upon stream stop ?

No, it does not have that much memory.

> [@zvivered](#):
>
> Can you please explain the losses we are getting ?

Perhaps it could be that your host system does not like many small USB transfers. By default software aims to transfer data in ~100us chunks.  
Configure your parameters, then try to run `limeTRX --log debug --rxPacketsInBatch=64` it will print the data rate, see if changing the packets in batch count has any effect for you.

> [@zvivered](#):
>
> Is there a paid support plan for this product ?

Tagging, @andrewback

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<div class="post-metadata">

**Author:** ![andrewback](https://avatars.discourse-cdn.com/v4/letter/a/22d042/32.png) [@andrewback](https://discourse.myriadrf.org/u/andrewback)\
**Post date:** [14 August 2026 19:22 UTC](https://discourse.myriadrf.org/t/limesdr-runtime-warning-in-fft-view/13289/6 "2026-08-14T19:22:09Z")

</div>

> [@zvivered](#):
>
> Is there a paid support plan for this product ?

There isn’t a general paid support plan for the SDRs, but commercial support can be arranged subject to requirements etc. I’ll drop you a line.