It could be the computer spec.. Depending on the CPU in the HP Pro and the demand placed on the computer by the particular piano sound you're using, the computer could be crapping out..
- When playing/recording sample-based virtual instruments, the more notes played simultaneously the more strain is placed on the computer resources
- Some virtual instruments [like Native Instruments', for example, or modeled instruments] may put more strain on computer resources than others [like simpler instruments that come with a DAW]
- 8GB RAM could be ok for some things, but 16GB is usually recommended these days
One setting you should look at is the RAM Buffer setting, which should be somewhere in the DAW/application audio Preferences. You'll see options: 32, 64, 128, 256, 512, 1024. Lower values induce less latency (timing lag when playing) but put more strain on computer resources; higher settings relieve that strain but may make it uncomfortable to play live due to increased latency [delay/lag in response]. Anything higher than 256 may be hard to play through; anything lower than 128 -- especially with an older/less powerful computer -- may result in clicks/glitches/dropouts. You should check your current setting, and if it's low, try increasing it to the next higher level one value at a time until you find a setting that works reliably and is still comfortable to play live.
- If the piano sound is a sample-based sound and the instrument is set to load all samples into RAM, then your 8GB might not be enough to handle a large instrument
- If it's set instead to stream samples from hard disk [usually the current default], and the samples themselves -- the audio files -- are sitting in a hard drive that's too slow or too full, that could result in problems
That setting should be found somewhere in the Instrument's Settings/preferences.
If the RAM buffer value is already at a high value, and your Instrument is set to stream audio from a HD that's fast and has plenty of free space, then that computer may just not be powerful enough for that particular patch..