msi2500 driver conflicts

Look at dmesg to see if your system has loaded device drivers for the SDR module. They are incompatible with the binary-only driver. Relevant output:

[20084.148384] msi2500 3-2:1.0: Registered as swradio0
[20084.148386] msi2500 3-2:1.0: SDR API is still slightly experimental and functionality changes may follow

In this case, edit /etc/modprobe.d/blacklist.conf and add:

blacklist sdr_msi3101
blacklist msi001
blacklist msi2500

Then, unplug the SDRPlay, remove the offending modules and restart the module loading service (or whatever loads the modules on your Linux distribution):

sudo rmmod msi001 msi2500
sudo systemctl restart systemd-modules-load.service