TP-LINK MR3020 sta mode (wireless) interference.
Hi, everyone
OpenWRT Version: Attitude Adjustment , r38863
Shairport Fork: https://github.com/sm3rt/OpenWRT-ShairPort
I have compiled Shairport with the latest Attitude Adjustment and all is working well apart from one small problem that has me pulling my hair out for a week.
When I have my MR3020 connected directly to another access point in my network and have shairport streaming through its ethernet port I have (near) perfect audio.
When I switch to STA mode and connect my MR3020 as a client over wireless I start to have small POP´s, clicks and background noise / interference.
After a week of digging around I have come to the conclusion that it is radio wave interference caused by the internal aerial, or lack of one. Is any one able to confirm simular results?
I am using ALSA to direct Shairports output directly to the USB DAC:
asound.conf
pcm.!default {
type plug
slave.pcm "hw:0,0"
}
Shairport is up and running correctly with config:
config airplay
option bname 'Numbnuts'
option initbuf 300
option daemonize true
USB DAC status is consistent when connected through wireless client or through ethernet. I was originally hoping that it was some sort of resampling going on when connected through wireless.
#cat /proc/asound/card0/stream0
C-Media Electronics Inc. USB PnP Sound Device at usb-ehci-platform-1, full spee : USB Audio
Playback:
Status: Running
Interface = 1
Altset = 1
URBs = 2 [ 1 1 ]
Packet Size = 200
Momentary freq = 44100 Hz (0x2c.199a)
Interface 1
Altset 1
Format: S16_LE
Channels: 2
Endpoint: 1 OUT (ADAPTIVE)
Rates: 48000, 44100
Capture:
Status: Stop
Interface 2
Altset 1
Format: S16_LE
Channels: 1
Endpoint: 2 IN (ADAPTIVE)
Rates: 48000, 44100
#cat /proc/asound/card0/pcm0p/sub0/status
state: RUNNING
owner_pid : 949
trigger_time: 6835.421757873
tstamp : 10366.601723231
delay : 65536
avail : 44
avail_max : 55372
-----
hw_ptr : 155723604
appl_ptr : 155789096
Shairport Running with wireless connection
#shairport ... -vv
Failed to bind to address ::
Bound to address 0.0.0.0
avahi: avahi_register
avahi: register_service
Listening for connections.
culling threads.
new RTSP connection
received request: ANNOUNCE rtsp://192.168.10.102/3468496320 RTSP/1.0
CSeq: 1
Content-Type: application/sdp
Content-Length: 574
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
sending response: RTSP/1.0 200 OK
CSeq: 1
Audio-Jack-Status: connected; type=analog
received request: SETUP rtsp://192.168.10.102/3468496320 RTSP/1.0
CSeq: 2
Transport: RTP/AVP/UDP;unicast;interleaved=0-1;mode=record;control_port=6001;timing_port=6002
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
rtp_setup: cport=6001 tport=6002
rtp listening on port 43915
sending response: RTSP/1.0 200 OK
CSeq: 2
Audio-Jack-Status: connected; type=analog
Transport: RTP/AVP/UDP;unicast;interleaved=0-1;mode=record;control_port=6001;timing_port=6002;server_port=43915
Session: 1
received request: RECORD rtsp://192.168.10.102/3468496320 RTSP/1.0
CSeq: 3
Session: 1
Range: npt=0-
RTP-Info: seq=46817;rtptime=748372815
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
sending response: RTSP/1.0 200 OK
CSeq: 3
Audio-Jack-Status: connected; type=analog
received request: SET_PARAMETER rtsp://192.168.10.102/3468496320 RTSP/1.0
CSeq: 4
Session: 1
Content-Type: text/parameters
Content-Length: 20
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
volume: -13.500604
sending response: RTSP/1.0 200 OK
CSeq: 4
Audio-Jack-Status: connected; type=analog
received request: SET_PARAMETER rtsp://192.168.10.102/3468496320 RTSP/1.0
CSeq: 5
Session: 1
Content-Type: text/parameters
Content-Length: 20
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
volume: -13.500604
sending response: RTSP/1.0 200 OK
CSeq: 5
Audio-Jack-Status: connected; type=analog
syncing to first seqno B6E1
buffering over. starting play
WARNING: requesting resend on 2 packets (B86F:B870)
established desired fill of 298.965000 frames, so output chain buffered about 1.035000 frames
received request: OPTIONS * RTSP/1.0
CSeq: 6
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 1626069284
sending response: RTSP/1.0 200 OK
CSeq: 6
Audio-Jack-Status: connected; type=analog
Public: ANNOUNCE, SETUP, RECORD, PAUSE, FLUSH, TEARDOWN, OPTIONS, GET_PARAMETER, SET_PARAMETER
+++++++++
+++++++++
.........
Shairport Running with wired connection
#shairport ... -vv
Failed to bind to address ::
Bound to address 0.0.0.0
avahi: avahi_register
avahi: register_service
Listening for connections.
culling threads.
new RTSP connection
received request: OPTIONS * RTSP/1.0
CSeq: 1
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
Apple-Challenge: 2SIjBWArEnXtMGSL8S9yHQ
sending response: RTSP/1.0 200 OK
Apple-Response: AK86+xIYj4Pmn5KOnZ2YokfMlhjQrSr9A0qIGPHIgIQpXaUxru6Unm1eGkH/oP3eF66ywN3JGtcRpCRYLEIdlPDanwdSczZUhlTLyNNUFkkbFLJLs/mel8ERYd6UaurkrY70ci1pVL1ZvMXDoAjpP59VzncybKPmlZPtScI0m3djNT9kS6v+jzj87woHfPCnB/iXFhDauMZY7gv84LWXTVuu1bpV8ru41mduJFxmv71TZMxtlaULtqdMEXr+RIuStZLaeP5ZUzGLMYV61NKEmVGG4BefbPX2TGb+mmD1+XRt2ZSyUMoHhZzpzqtzS5ujZdehkSInGrmcx4lyI4Ye3g
CSeq: 1
Audio-Jack-Status: connected; type=analog
Public: ANNOUNCE, SETUP, RECORD, PAUSE, FLUSH, TEARDOWN, OPTIONS, GET_PARAMETER, SET_PARAMETER
RTSP connection closed
closing RTSP connection
terminating RTSP thread
culling threads.
one joined
new RTSP connection
received request: ANNOUNCE rtsp://192.168.10.102/3468498685 RTSP/1.0
CSeq: 1
Content-Type: application/sdp
Content-Length: 573
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
sending response: RTSP/1.0 200 OK
CSeq: 1
Audio-Jack-Status: connected; type=analog
received request: SETUP rtsp://192.168.10.102/3468498685 RTSP/1.0
CSeq: 2
Transport: RTP/AVP/UDP;unicast;interleaved=0-1;mode=record;control_port=6001;timing_port=6002
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
rtp_setup: cport=6001 tport=6002
rtp listening on port 53127
sending response: RTSP/1.0 200 OK
CSeq: 2
Audio-Jack-Status: connected; type=analog
Transport: RTP/AVP/UDP;unicast;interleaved=0-1;mode=record;control_port=6001;timing_port=6002;server_port=53127
Session: 1
received request: RECORD rtsp://192.168.10.102/3468498685 RTSP/1.0
CSeq: 3
Session: 1
Range: npt=0-
RTP-Info: seq=27452;rtptime=3269296137
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
sending response: RTSP/1.0 200 OK
CSeq: 3
Audio-Jack-Status: connected; type=analog
received request: SET_PARAMETER rtsp://192.168.10.102/3468498685 RTSP/1.0
CSeq: 4
Session: 1
Content-Type: text/parameters
Content-Length: 20
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
volume: -13.500604
sending response: RTSP/1.0 200 OK
CSeq: 4
Audio-Jack-Status: connected; type=analog
received request: SET_PARAMETER rtsp://192.168.10.102/3468498685 RTSP/1.0
CSeq: 5
Session: 1
Content-Type: text/parameters
Content-Length: 20
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
volume: -13.500604
sending response: RTSP/1.0 200 OK
CSeq: 5
Audio-Jack-Status: connected; type=analog
syncing to first seqno 6B3C
buffering over. starting play
established desired fill of 297.843000 frames, so output chain buffered about 2.157000 frames
received request: OPTIONS * RTSP/1.0
CSeq: 6
User-Agent: iTunes/11.1.3 (Windows; Microsoft Windows 7 x64 Home Premium Edition (Build 7600)) AppleWebKit/536.30.1
Client-Instance: 76E89ACF4B76D5FF
DACP-ID: 76E89ACF4B76D5FF
Active-Remote: 3022224022
sending response: RTSP/1.0 200 OK
CSeq: 6
Audio-Jack-Status: connected; type=analog
Public: ANNOUNCE, SETUP, RECORD, PAUSE, FLUSH, TEARDOWN, OPTIONS, GET_PARAMETER, SET_PARAMETER
+++++++++
+++++++++
+++++++++
.........
I am still hoping I am able to still fix this through configurations. If anyone can shed any light on this would be much appreciated
Thanks in advance
Jack
(Last edited by BURR on 28 Nov 2013, 16:59)