I have included sample output from a variety of commands below which clearly details the underlying OS sees the URI as it should, and the given address etc...
see the example output below...
taken from /var/log/asterisk/messages
[Jul 7 22:19:46] WARNING[6703] chan_usbradio.c: Loaded parameters from usbradio_tune_usb.conf for device usb .
[Jul 7 22:19:46] WARNING[6703] chan_usbradio.c: Unable to re-open DSP device 1 (usb): No such file or directory
$ cat /proc/asound/cards
0 [ALSA ]: bcm2835_alsa - bcm2835 ALSA
bcm2835 ALSA
1 [Device ]: USB-Audio - USB PnP Sound Device
C-Media Electronics Inc. USB PnP Sound Device at usb-3f980000.usb-1.1.3, full s
$ lsusb
Bus 001 Device 004: ID 0bda:2838 Realtek Semiconductor Corp. RTL2838 DVB-T
Bus 001 Device 005: ID 0d8c:013a C-Media Electronics, Inc.
Bus 001 Device 006: ID 0424:7800 Standard Microsystems Corp.
Bus 001 Device 003: ID 0424:2514 Standard Microsystems Corp. USB 2.0 Hub
Bus 001 Device 002: ID 0424:2514 Standard Microsystems Corp. USB 2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
$ cat /etc/asterisk/usbradio_tune_usb.conf
[usb]
; name=usb
; devicenum=1
devstr=1-1.1.3:1.0
rxmixerset=500
txmixaset=450
txmixbset=500
rxvoiceadj=0.557342
rxctcssadj=0.930165
txctcssadj=220
rxsquelchadj=754
fever=1