Low signal--what can I do inside?

We have Time Warner digital cable and have had chronic problems with mostly HD channels (some SD channels) having various artifacts and what not There's maybe a 100 foot RG6 run from the road to our house. And once inside the house, there's a 2 way splitter that goes off to the cable modem, which works great 99% of the time, so I'm not worried about that. After the 2 way splitter, it goes to a 6 way Leviton 47690-6C2 splitter to feed all the rooms throughout the house.

Cable tech just came inside and said we're on the verge of the low side. But he didn't test anything after the 6 way splitter, assumingly because they don't support it. He tested outside and found 1 foreign channel to be bad, enough to get a lineman out here and hopefully fix things, but I've heard this story before.

I like to tackle problems from multiple angles so I'm wondering is there anything I can inside the house to improve things as that's my responsibility? Currently we don't actually need the 6 way splitter, as we have only 3 devices in the house that need cable. 1 cable modem, and 2 dvrs. Would getting a 2 or 3 way splitter to replace the 6 way help much? (leaving towards a 3-way in case we want cable in another room in the future)
Would even reducing from 6 to a 3 way even help much?

Or perhaps getting a signal booster of some sorts? But sounds like that would be too much boost and I'd need some kind of attenuator after that.

Thanks for the response, yeah, I suppose it's easy and cheap enough to get a 3-way splitter when it's actually needed. I'm getting one of these:
http://www.amazon.com/gp/product/B00...A2FJC5RUG7GN9R

During my research, this is the first I've ever heard about about end caps with cable, although I've done it with 10 base 2 networking before. My current 6-way splitter doesn't have a single end cap on it. Does this mean I'd get a better signal if I removed all lines that aren't used and replace them with end caps?

Turns out some linemen came out later the same day and knocked on my door wondering how it was looking. They ended up replacing the 2-way DC9 tap and 6-way with a single balanced 3-way and all is fantastic. They couldn't believe the original guy who came out didn't suggest getting rid of it, but then I didn't really ask about it, as I didn't know how much signal was lost through those things at the time. FYI, one of the linemen was "in training" hence the two of em.

Current signal page:

Frequency 669000000 Hz Locked
Signal to Noise Ratio 38 dB
Power Level 9 dBmV

Upstream Value
Channel ID 9
Frequency 31000000 Hz Ranged
Power Level 39 dBmV

That's good to know. Before I had a DC-9 tap (tap going to the cable modem) before the 6-way splitter. So I lost 9db after the tap, and the 6-way probably lost me around 9 db or more as well, so the combination of losses on both of them was most likely my issue.

Not too much wire going into the sets as we live in a newer ranch, with quad shielded RG6.

I believe the tap was going to the modem and out to the 6-way.

Ahhh, I had it backwards. 9db seems like a huge loss for a simple 2-way splitter, but I guess the point is there's almost no loss on one leg.