hmmm... it sounds like you should have purchased a PRO-HD for the internal tuner. then you could just have one Slingbox. and if your wife was watching the cable box int hat room, you could switch to the internal tuner and just watch stuff that was on basic cable without bugging her.
if you solo is new enough and you can return it, i would suggest that.
then just one purchase and no new cable fees.
I largely agree with what the other have posted. A Slingbox with a built in tuner provides a lot of flexibility assuming you have analog cable support. Be aware that analog cable support is on the decline. Some provider are dropping channles very quickly.
There are plenty of other options..
Move the existing Slingbox to the bedroom.
Buy a used Classic.
Sell the Solo and buy a Pro HD.
In my case I have 2 Pros and a Classic that are 'multi-source' as well as a Pro HD and a Solo attached to dedicated boxes.