[dba-Tech] Unstable Wireless Netowrk

I've got four machines hardwired in a wireless router and one wireless.  The wireless has been working pretty well for several months.  Suddenly it's become very unstable, dropping in and out, being available and then not, at random.  

Could be the wireless router, I suppose getting flaky.  But I'm wondering if some windows update might be responsible, requiring something new that I'm not aware of.  

We're not using encryption.  Could another wireless network in the neighborhood be causing some problem?

Anyone know of anything like that?

Rocky