Serious issue with Sirus!

In my previous car (TSX) I had XM radio and I've been pretty happy with it. I had no issues with losing the signal during driving in the trees, but it's not the case with Outlander & Sirus. Signal would constantly cut out if driving in the woods or between tall trees. Has anyone else noticed that? Is there a solution?

I had this problem with xm too. Somedays is better than otherdays in the outlander. I can drive the same roads and it will be hit or miss with the trees.

Is it possible your XM recorded a few minutes into memory? I noticed this with my sirius one records about 20m into memory and the other dumps the signal when I go through the trees. Also location of the antenna makes a difference but with factory you dont have control over that.

I have this same issue in my lancer with Sirius -- luckily the roads I drive on every day don't usually affect it though.  However, I do recall back when I had a portable Sirius radio (mounted to the windshield of my old car) I pretty much never had a signal drop out with it.  The few times it would was usually because I stopped the car right in a huge bunch of tall trees.  But when driving, it seemed nothing would drop out the signal (note: no terrestrial antennas in range of here).

Note that the Sirius satellites are geosynchronous -- meaning they aren't at a fixed position in the sky, but move around in a 24-hour orbit.  That is most likely why some days the roads you drive on don't cause problems where other days they do.  It also explains why every evening I can pick up the radio inside my closed garage, but only in the evening.  Wikipedia has an explaination if anybody's curious.

Does anybody know if the sirius module in the mitsu outlander/lancer (with MMCS) can receive sirius' terrestrial broadcasts in addition to the satellites?  Is the antenna integrated in the module?

We don't have trees in San Diego ;), but it does cut out under bridges. 

I live on the hill with a lot of trees around and it constantly cuts out in the same area where I drive through every day. It cuts out under the bridges, in the garage and in the building where I work at, but that's normal, XM had the same issue.

Satellites like the ones that Sirius and XM use work off of line of sight. So, trees and bridges will affect the signal.

it makes sense, but XM did not cut out when I was driving in the same area with trees, so my conclusion that antenna is weaker in outlander

Mitsu has apparently had some issues with their antennas.  Your best bet is to change the antenna.  I actually took a spare antenna I had from a GT Streamer and put it in the rear wing.  It's magnetic and sits on the steel ledge under the wing - then I ran the wiring under the headliner up to the front and plugged it into the satellite receiver.
 
Great reception and no problems so far with it cutting out due to trees, etc.