sink_process_msg: not running error during speaker-test

[guyuming76]

i am using xfreerdp to connect to xrdp on the same computer with pulse sound.

inside xfreerdp session, i run speaker-test, but the noise stutters, it stops for several seconds every tens of seconds.

i can see error message "sink_process_msg: not running" in syslog.

after i set the log-level to debug in /etc/pulse/daemon.conf, i can see what follows with command:
guyuming@gymDesktop:/var/log$ tail -n 5000 syslog|grep 'Free|Created|sink_process_msg: not running'
Jan 20 13:59:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 13:59:50 gymDesktop pulseaudio[11432]: Freeing input 152 "ALSA Playback"
Jan 20 13:59:50 gymDesktop pulseaudio[11432]: Created input 153 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 13:59:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:10 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:10 gymDesktop pulseaudio[11432]: Freeing input 153 "ALSA Playback"
Jan 20 14:00:10 gymDesktop pulseaudio[11432]: Created input 154 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:00:10 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:30 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:30 gymDesktop pulseaudio[11432]: Freeing input 154 "ALSA Playback"
Jan 20 14:00:30 gymDesktop pulseaudio[11432]: Created input 155 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:00:30 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:00:50 gymDesktop pulseaudio[11432]: Freeing input 155 "ALSA Playback"
Jan 20 14:00:50 gymDesktop pulseaudio[11432]: Created input 156 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:00:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:10 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:10 gymDesktop pulseaudio[11432]: Freeing input 156 "ALSA Playback"
Jan 20 14:01:10 gymDesktop pulseaudio[11432]: Created input 157 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:01:10 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:30 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:30 gymDesktop pulseaudio[11432]: Freeing input 157 "ALSA Playback"
Jan 20 14:01:30 gymDesktop pulseaudio[11432]: Created input 158 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:01:30 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running
Jan 20 14:01:50 gymDesktop pulseaudio[11432]: Freeing input 158 "ALSA Playback"
Jan 20 14:01:50 gymDesktop pulseaudio[11432]: Created input 159 "ALSA Playback" on xrdp-sink with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:01:50 gymDesktop pulseaudio[11432]: sink_process_msg: not running

and its sound OK if i run speaker-test on the same computer, but on inside a xfreerdp session:
guyuming@gymDesktop:/var/log$ tail -n 500 syslog|grep 'Free|Created|sink_process_msg: not running'
Jan 20 14:06:02 gymDesktop pulseaudio[1470]: Freeing input 48 "ALSA Playback"
Jan 20 14:06:02 gymDesktop pulseaudio[1470]: Created input 49 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:06:13 gymDesktop pulseaudio[1470]: Freeing input 49 "ALSA Playback"
Jan 20 14:06:13 gymDesktop pulseaudio[1470]: Created input 50 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:06:24 gymDesktop pulseaudio[1470]: Freeing input 50 "ALSA Playback"
Jan 20 14:06:24 gymDesktop pulseaudio[1470]: Created input 51 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:06:35 gymDesktop pulseaudio[1470]: Freeing input 51 "ALSA Playback"
Jan 20 14:06:35 gymDesktop pulseaudio[1470]: Created input 52 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:06:46 gymDesktop pulseaudio[1470]: Freeing input 52 "ALSA Playback"
Jan 20 14:06:46 gymDesktop pulseaudio[1470]: Created input 53 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono
Jan 20 14:06:57 gymDesktop pulseaudio[1470]: Freeing input 53 "ALSA Playback"
Jan 20 14:06:57 gymDesktop pulseaudio[1470]: Created input 54 "ALSA Playback" on alsa_output.pci-0000_00_1b.0.analog-stereo with sample spec s16le 1ch 48000Hz and channel map mono