So here's the basic setup I've got. I've got a V3 RTL-SDR dongle attached to a Raspberry Pi, which runs SpyServer to allow remote control of it.

I can connect to it just fine from my laptop (running Xubuntu 18.04) via gqrx, and I can use SDRSharp on a Windows tablet as well.

However, these are devices that I don't have connected/running 24/7 so I set up an Xubuntu 18.04 VM under Proxmox with gqrx. However, with an identical default.conf file to my laptop (I literally used rsync to copy it over), gqrx will crash with the message:

Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock

RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (hw:1,0), Device or resource busy.



Using PlutoSDR URI = ip:pluto.local
ERROR: Unable to find host: Name or service not known
ERROR: Unable to find host: Name or service not known
terminate called after throwing an instance of 'std::runtime_error'
  what():  Unable to create context
Aborted (core dumped)

Although there's sound errors, I've verified that the sound output does seem to work (can watch Youtube videos and stuff).

The device string is:

host=192.168.0.15,port=5555,spyserver=0

If I change the host to "rtl_tcp", then gqrx will hang and not start. Running wireshark shows that there seems to be an infinite series of packets sent between the systems. Spyserver does not, however, indicate that a connection check has been made, and the packets seem to be a set of request/acknowledgement packets.

Changing the string to a simple

rtl_tcp=192.168.0.15:5555

Does allow the gui to spawn, but no audio data is received, and only a handful of packets are exchanged. Spyserver again does not note any successful connections.

I'm sort of at a loss here because as far as I can tell, it should work, but it's just not working.

As a note, the first device string is again, the one that my laptop uses and it works just fine on there.

EDIT: I'm actually leaning a bit more towards it being a sound issue of some sort; I've installed a USB headset and done a USB-passthrough to the VM to give it another option for sound. When I did this, I was able to get a very symmetrical looking FFT output which spiked when I tapped the headset's microphone, and moved in time to other audio sources I tried (it makes a very interesting audio visualizer for Youtube videos). So it seems something is holding up the sound hardware and GQRX isn't quite able to cope with it. I'll keep taking a look and poking around to see if there's anything I can do to fix it.