Flac format files playing problem on R-N500

Hi,
I just started to use serviio with my new network player Yamaha R-N500.
Serviio is installed on pc windows 7 machine.
Have several albums in flac format on pc.
Some of albums play normal on my Yamaha device using dlna feature, some of them are buffering after 5s of play, then play for several seconds and buffering again and so on.

Maybe someone could direct my where to search for problem.
Adding media info of two files examples one of then play normal another with pauses.

Play normal:
...
Audio
Format : FLAC
Format/Info : Free Lossless Audio Codec
Duration : 4mn 7s
Bit rate mode : Variable
Bit rate : 2 700 Kbps
Channel(s) : 2 channels
Sampling rate : 96.0 KHz
Bit depth : 24 bits
Stream size : 79.7 MiB (100%)
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)

Play with pauses:
Audio
Format : FLAC
Format/Info : Free Lossless Audio Codec
Duration : 4mn 15s
Bit rate mode : Variable
Bit rate : 2 808 Kbps
Channel(s) : 2 channels
Sampling rate : 96.0 KHz
Bit depth : 24 bits
Stream size : 85.4 MiB (100%)
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)

Tried one more thing.
R-N500 has USB port. Wrote files to USB drive. When connected directly, not per dlna plays perfectly.

[atc98092]

Tried one more thing.
R-N500 has USB port. Wrote files to USB drive. When connected directly, not per dlna plays perfectly.

Remember that playback via DLNA is a different protocol than from the USB port. Many devices can play via USB that won't play via DLNA.

Are you using wireless to connect the Yamaha? Possible there's a connection issue or interference on the Wi-Fi channel you are using. In the 2.4 GHz Wi-Fi band, there are often numerous household devices that could interfere, such as cordless phones.

Remember that playback via DLNA is a different protocol than from the USB port. Many devices can play via USB that won't play via DLNA.

Are you using wireless to connect the Yamaha? Possible there's a connection issue or interference on the Wi-Fi channel you are using. In the 2.4 GHz Wi-Fi band, there are often numerous household devices that could interfere, such as cordless phones.

Nope, wired devices no wireless used.
Will try another program as dlna provider.