Problem from Theta Digital

"Theta Digital DSPro Prime II"

Did anyone have same problem.. I bought the machine for a year and I’ve connected with optical cable from CD

Just now, whenever I turn on , the light from “Lock”. is flashing.. and sound signal come out not smooth … have to wait for 3 min. until flashing gone and appeared “Lock” light on typically ,sound came back to normal and smooth… Is that typical for this machine.. This problem just happens..or because of to cold..??? have to wait like tube?

Please me everyone.
Thank you.