I wouldn't be too worried. Initially when Spektrum came out I think HH made a couple serious mistakes. The first was to promote the system as impervious to interference, the second thing was to equip the systems with 4.8V RX batteries.
The other thing that I highly recommend doing and especially with Spektrum gear when using satellite receivers is do multiple range checks. For example, with a gasser I do a range check with the engine off. Get out to the edge of range with the TX set to the reduced power setting. Have a helper move the airplane 360 degrees taking note if any drop out occur. Then do the same check with the engine running. When doing this I am looking for at least 250' of range at low power. If I fail to get that or I get more then a 10% reduction with the engine running, I will start to try different antenna locations and orientations. It does not take much to block 2.4 GHZ. Having the antenna blocked by a fuel tank can be enough. It's also important to realize the emitting pattern off the TX antenna. It is better off the sides of the antenna as opposed the tip. You never want to point the TX antenna at the airplane. For Futaba and Hitec gear you want to orientate the antennas where one is horizontal and one vertical. For Spektrum I follow that same orientation but with a satellite RX I will put one at 45 degrees and placed in the fuselage as high as possible, in the canopy or turtle deck. IMO with 2.4 antenna placement is even more critical then it was with 72 MHZ in spite of the fact that on board equipment creates less issues.