Tivo Series 2 Dual Tuner ( S2 DT) locking up more often now?

It may be IR interference. Have you added CFL lights or a new TV? The power saving mode and backlight settings on some flatscreens can cause that kind of problem.

The next time it happens, try shining a bright flashlight directly on the IR sensor in the front panel (it's in the middle right below the faceplate). That will force the receiver to reset and recalibrate without a reboot. If that fixes the problem it's almost certainly interference. If not, your hard drive may be failing.

I'm still running 4 of them without a single problem. TiVo hasn't updated the software for those units in a long time and there have been no recent updates.

 

Allow me to suggest that you get the free version of TiVo Desktop and copy (they call it 'transfer') all of the recorded shows you want to keep, and then remove the drive(s) from your TiVo and do a truncated backup to keep in a safe place for future reference, and then run the manufacturer's diagnostics on it(them).

You should also go read the "List of SATA to PATA (IDE) adapters, please add yours" thread

http://www.tivocommunity.com/tivo-vb/showthread.php?t=416883

to find out what SATA drives and adapters you may want to think about getting in the not too distant future if necessary, and it wouldn't hurt to check out the

Drive Expansion and Drive Upgrade FAQ

http://www.tivocommunity.com/tivo-vb/showthread.php?t=370784

either. It started out Series 3-centric but there's a lot of info in there on what drives do or don't have what problems in many different TiVo models.

I'm not promising you that your drive(s) is(are) going bad, I'm saying in case that's the cause, here's how to get ready for it.