Hello guys !
does anyone know how to disable auto-tune on phoenixminer ?
Because even with the parameters below given by @Zorg33 i got phoenixminer reboot regularly which is painful.

Weaker Vega 64 or flashed 64 (Samsung) - use if lucky timings aren't stable:
--CL 19 --RAS 30 --RCDRD 12 --RCDWR 6 --RC 44 --RP 13 --RRDS 5 --RRDL 5 --RTP 4 --FAW 18 --CWL 6 --WTRS 4 --WTRL 9 --WR 15 --WRRD 1 --RDWR 18 --REF 17000 --RFC 248

So until finding the sweet spot for my vega 56 flashed to 64, i just updated the REF to 17000 for which i get 47+ mhs.

Thanks in advance for your help.