Comcast XFINITY TV → Comcast and TiVo dual tuner

Alright, let me start off by saying I've searched the forums and not specifically found my answers, so I'm going so far as to post and beg for some advice from knowledgeable folks.

I've got Comcast digital classic and a TiVo series 2 dual-tuner... The wiring back there has become unfortunately the spaghetti bowl, so here's the explanation.

It goes from wall jack to a "genisys 2 -3.5db" splitter (acquired from a comcast tech who was out) which feeds coax into the cable box and also the TiVo. The cable box then feeds the triple-wire connectors back into the TiVo (this gives it the dual-tuner ability) - from the TiVo another set of triple-wires goes to an RF modulator (cuz my TV is older and only has the coax connection on the back) which feeds coax into the TV itself.

This setup works perfectly most times, but lately I'm getting the Comcast "please wait, this channel will be available shortly" message on many channels unless I take the first splitter out of the deal. The TiVo loses its dual tuner ability, but I get channels properly. When this happens the TiVo pops up the annoying "searching for signal on basic cable in" message cuz its expecting two signals and not getting them.

So what I think happening is I'm probably losing signal strength due to the splitter? Or could it bad cables themselves? Why would it have worked so far fairly well, and then fail on me? How does TiVo expect people to hook all this up when Comcasts support immediately tells me to hook directly up to their cable box and not have any splitters in the way?

Is this a common problem? Is there something I can do to fix this?

Thanks in advance!

Probably a bad splitter. Sometimes they just go bad. Things degrade over time. Nothing lasts forever.

Try another splitter. If that doesn't fix it, something went wrong further down the chain.

Either the splitter is bad or the signal level is too low.

Splitter
Signal
Noise

Next time you get the message check the diagnostics.

If its a motorola hit Power then OK. Scroll to In Band Status in the diagnostic menu.
If the SNR says POOR or even FAIR while your channel is sayig One Moment Please then it is noise related.
Loose connections, squirrel chew, etc.

If the SNR states "GOOD" then it is most likely signal related.
There is no way to know what your signal level is without the proper equipment but assume about 10db where it comes into your home and subtract all the loss for any splitters you have.

If your still in the positive range then we can assume something plant wise happened outside the home and your signal dropped due to something else.

Or, bad spliter.

The splitter that the Comcast tech gave me was the 2nd splitter I had. When he was out a few weeks ago (they had like a 10 day outage in my building, but that was another rant) he replaced the 5-900mhz splitter I had and all was fine until just the other day when it started doing this "channel will be available shortly" thing again.

The only other thing 'further down the chain' between the cable box and the cable coming out of the wall is the 3' cable I'm using after the splitter. I'll dig up a replacement cable and see if that fixes it... Can those cables be rated so differently as to impede the signal enough to mess me up like this?

Would a lower power coax amplifier work for me here? I'd hate to blow out my cable box and TiVo all at once, though.