i wanted to say this did work on my raspberry pi 3b running raspberry pi os 2020-08-20-raspios-buster-armhf.zip
i do have a problem with my board appears with that mcu error 5 Rx calibration.
here is my output after i did a clean install then updated and then installed spectrogram
pi@raspberrypi:~ $ spectrogram
2020-10-15 18:39:19.578 | WARNING | main:warn_temperature:16 - Cool your LimeSDR or risk damage!
2020-10-15 18:39:21.875 | INFO | main:docker_pull:20 - Pulling latest docker image…
Error response from daemon: Get https://registry-1.docker.io/v2/: dial tcp: lookup registry-1.docker.io on 8.8.8.8:53: dial udp 8.8.8.8:53: connect: network is unreachable
2020-10-15 18:39:22.180 | INFO | main:probe_devices:83 - Probing for LimeSDR-Mini devices…
2020-10-15 18:39:31.505 | INFO | main:probe_devices:106 - remote_available=False, local_available=True, local_fpga_ok=True
2020-10-15 18:39:31.507 | INFO | main:docker_start_server_daemon:58 - Starting server daemon…
8e3dde5dbdd892667ce8f92e4d80b071d3da4e938f1f1459ed095160bd8906bc
2020-10-15 18:39:34.804 | INFO | main:docker_start_gqrx:48 - Starting gqrx…
2020-10-15 18:39:34.806 | WARNING | main:warn_temperature:16 - Cool your LimeSDR or risk damage!
- Starting system message bus dbus
…done. - Starting Avahi mDNS/DNS-SD Daemon avahi-daemon
…done.
QStandardPaths: error creating runtime directory /tmp/runtime-root: No such file or directory
libEGL warning: DRI2: failed to authenticate
[INFO] Make connection: ‘LimeSDR Mini [USB 2.0] 1D3BD0C4F0CDFF’
[WARNING] This version of LimeSuite only works for the ‘spectrogram’ application!
[INFO] Device name: LimeSDR-Mini
[INFO] Reference: 40 MHz
[INFO] Selected TX path: Band 2
[INFO] Selected RX path: LNAW
[INFO] LMS7002M calibration values caching Enable
setting samples rates to 80 Msps…
[INFO] Setting oversampling of 2
[INFO] Selected RX path: LNAH
[INFO] Setting oversampling of 2
[INFO] RX LPF configured
[INFO] SoapyRemote::setupRxStream(remoteFormat=CS16, localFormat=CS16, scaleFactor=2048, mtu=2120, window=44040192)
[INFO] Server side stream bound to [::ffff:172.17.0.1]:44507
[WARNING] StreamEndpoint resize socket buffer: set 43008 KiB, got 176 KiB
[INFO] Configured sender endpoint: dgram=2072 bytes, 512 elements @ 4 bytes, window=176 KiB
[WARNING] StreamEndpoint resize socket buffer: set 43008 KiB, got 176 KiB
[INFO] Configured receiver endpoint: dgram=2072 bytes, 512 elements @ 4 bytes, window=176 KiB
[INFO] Selected RX path: LNAH
[INFO] Selected RX path: LNAH
[INFO] RX LPF configured
[INFO] Selected RX path: LNAW
[INFO] Selected RX path: LNAH
[INFO] Selected RX path: LNAH
[ERROR] Rx calibration: MCU error 5 (Loopback signal weak: not connected/insufficient gain?)
2020-10-15 18:42:06.547 | INFO | main:main:167 - Killing local server…
spectrogram_server
2020-10-15 18:42:08.191 | INFO | main:main:170 - Done!
pi@raspberrypi:~ $
it does appear to be running ok but what about that error?
i wish i could get ‘spectrogram --server_only’ to work over wifi/lan from rpi3b to my laptops running ubuntu amd64 desktop 18.04/20.4 but no luck so far.
good to see it does work straight out the box with rpi3b and latest raspberry os as of today.
just keep limesdr-mini cool. mine was running at 26C but i have big heat sink and a house fan on it 
@andrewback