IR function goes away after re-imaged disk

Help! Sony IR blasters inop
Greetings! I have a Sony SVR-2000 with the latest 1.62 Oztivo image on it. I used to about once every three months or so have problems with IR codes working through the IR blasters to control a Foxtel Pace digital series STB.
Now even after I re-image the hard disk about 6 hours after it comes out of maintenance mode the IR blasters start to only give two digits instead of three. Then in a little while they stop all together. In the past a hard reboot usually fixed this now NOTHING WORKS! I need to know should I replace the IR blasters? Or just replace the Tivo as it is now about 4.5 years old. Its just strange how something can work fine and then about 2 hours later it doesn't work at all or improperly. Any ideas from the experts? I'm tired of troubleshooting this rig and about a hair away from turfing it.
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It *could* be a hardware fault but I've never seen anything like this. Anything is possible however. Shame you think that turfing the TiVo is your only option as they are very repairable.

Yeah I was just getting a bit miffed at playing with this thing so much to get it to work properly. Anyhow with the change of weather here in Sydney I have a theory. I think heat is a factor with my IR problem which would explain that the Tivo works fine for the first few hours after being unplugged for awhile and then eventually as it heats up ( and it was running around 40 yesterday ) it begins to fail. I"m going to try some extra fans I will add to see if it helps. I never had this problem before because we lived in Melbourne and never had a problem with things getting too hot in the house we lived in.
What do you think Mr. King?

I run TiVo's in test mode in a rack at around 55C to see if any faults appear. A healthy TiVo will not fail at this sustained temperature and if it does there is a hardware problem (obviously :) )

Your idea of testing further sounds good. My advice would be to run the TiVo with no cover on and a fan blowing into it. If your problem goes away then yes it is a mainboard hardware issue and will require further attention. The fact that you mention it will work fine for a few hours from cold does indicate something amiss somewhere. Attempting the above in an effort to keep it cooler will test and narrow it down to either a software (and therefore no change in fault behaviour) or hardware issues if the fault does not appear.

For some reason the old Oztivo image always worked best on this Tivo.
Do you know where I can find 1.50 image?
Thanks, I'm still having problems with the IR blasters working, sometimes they work sometimes not. weird maybe it is just slowly failing.

There is no difference between r1.5 and r1.62 as far as IR is concerned