ESP8266 crashes and restarts

[shkdxb]

using TinyRF_RX.h to receive string of 55 character. ESP8266 is receiving properly but suddenly once in a while it thorws exception and restarts, below are the exception details. if i comment the lines related to tinyRF, system is working normal.

-------------- CUT HERE FOR EXCEPTION DECODER ---------------

ets Jan 8 2013,rst cause:2, boot mode:(3,7)

load 0x4010f000, len 3424, room 16
tail 0
chksum 0x2e
load 0x3fff20b8, len 40, room 8
tail 0
chksum 0x2b
csum 0x2b
v0005e880
~ld