problem with preamp switching sources

Hello Everybody:

Last year I bought a cheap solid state remote-controlled (but I don't have the remote) Onkyo used preamp in order to deal with some issues in my system. I like it ok, except that sometimes it seems to experience electrical issues, particularly resetting my source to Tuner from CD.

This thing is inexpensive and I am not trying to fix it.

What interests me is to clear up the ignorance I seem to have of preamp issues. If I knew what "key words" to search, for this type of issue, perhaps I would not have to start a new thread and ask a question. I seem to rememember sometimes people talking about some preamps having this electrical problem? Is there a type of preamp in which it is common? Those that have remote controls?

I guess I will substitute in another preamp at some point, but in the process, I'd like to learn and better understand what is going on here.

Thanks to anyone who can clarify for me what is going on here.