I'm building a squeezebox compatible powered-speaker with the hifiberry amp and a pitft 2.8" touchscreen.
Everything is working on the original raspbian wheezy distribution using the custom kernel provided by Adafruit that has the driver for the pitft touchscreen.
To reduce the boottime I've switched to a new image based on raspbian Lenny with kernel 4.1.6 (the use of systemd helped me to reduce the boot time from 40s to 18s!). BUT: although the hifiberry amp is detected succesfully, I get no sound at all.Again I used the image provided byAdafruit that has the patches applied for the pitft touchscreen.
It is detected correctly:
$ dmesg|grep amp
[ 8.228998] snd-hifiberry-amp sound: ASoC: CPU DAI (null) not registered
[ 8.229039] snd-hifiberry-amp sound: snd_soc_register_card() failed: -517
[ 8.284915] snd-hifiberry-amp sound: ASoC: CODEC DAI tas5713-hifi not registered
[ 8.284959] snd-hifiberry-amp sound: snd_soc_register_card() failed: -517
[ 12.158943] snd-hifiberry-amp sound: ASoC: CODEC DAI tas5713-hifi not registered
[ 12.158988] snd-hifiberry-amp sound: snd_soc_register_card() failed: -517
[ 14.040797] snd-hifiberry-amp sound: tas5713-hifi <-> 20203000.i2s mapping ok
The mixer settings are correct:
Simple mixer control 'Master',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 248
Mono: 242 [98%]
Simple mixer control 'Channels',0
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: 0 - 248
Front Left: 239 [96%]
Front Right: 239 [96%]
$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_amp], device 0: HifiBerry AMP HiFi tas5713-hifi-0 
Subdevice #0: subdevice #0
But I hear nothing.... Since I only changed the SD card, it is probably not a hardware issue. How can I fix this? I'm currently investigation how to cross compile a kernel myself, but since that will take some time I decided to ask for help on this forum too.