snd_usb_pcm_delay 75 sound/usb/pcm.c substream->runtime->delay = snd_usb_pcm_delay(subs, snd_usb_pcm_delay 1691 sound/usb/pcm.c est_delay = snd_usb_pcm_delay(subs, runtime->rate); snd_usb_pcm_delay 5 sound/usb/pcm.h snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,