A technique I've learned recently is to use a side-chain enabled multi-band compressor to compress only the lower frequencies of the bass sound when the kick hits and leave its high end untouched. This way, you eliminate the level build up on the conflicting frequencies but the change isn't so obvious. This is probably common knowledge but I hadn't thought about it before. Unfortunately, Quantum isn't side-chain enabled (yet), so you have to do it manually with a BandSplitter, a Gravity and a merger.
Make sure none of your outputs are clipping (red light on master output). Otherwise the sound driver may decide how to handle that. It could choose a compression algorithm.
If your audio get transferred through some data compression (e.g. bluetooth) a poorly chosen codec can introduce masking as a compression artifact (see
@Jordi Moragues
's comment).
In theory it's possible that your kick contains the same frequency as your bass and some destructive interference is happening. This is very unlikely but changing the bass' pitch would solve this.
If you are just mixing both sounds (kick and bass) but they otherwise don't interact with each other (for example, by using side-chain compression), this might just be a psycho-acoustic effect. Check with the audio level meter if the loudness of your bass sound is being affected at all when the kick hits. The level should be constant. If you still hear this volume loss, some frequencies of the kick might be masking some frequencies of the bass when they sound together, therefore you seem to "lose" the bass a bit. You could alter the arrangement to get rid of simultaneous notes (this is common in EDM) or use EQ to correct the frequency conflict in simultaneous notes.
1.) Change your bass sound or your kick sound so they compliment each other better.
2.) Sidechain the bass out of the way with your kick
3.) Change your composition so the bass notes play in the space between the kick.