it's making a loud grinding or buzzing noise during the wash cycle, sounds like it's coming from the bottom

Diagnosis

The grinding or buzzing noise emanating from the bottom of your Samsung Bespoke DW80B7070AP is almost certainly caused by a foreign object—such as a shard of broken glass, a popcorn kernel, or a small piece of plastic—that has bypassed the filtration system and entered the wash pump impeller housing. When the pump engages to circulate water through the spray arms, the impeller spins at high speeds; if a hard object is lodged in the housing, it creates a mechanical "buzzing" or "grinding" sound as the impeller blades strike the debris. In some cases, this noise is not debris but a symptom of "cavitation" or a failing pump motor bearing, though this is less common in the Bespoke series. To confirm it is a debris issue, listen for the noise to start specifically when the wash cycle transitions from filling to circulating. If the noise is intermittent or changes pitch as the water level fluctuates, it is likely a loose object rattling within the sump cavity or the impeller shroud.

How to Fix It

Follow these precise steps to clear the pump and restore quiet operation:

1. Power down the unit completely. For safety, switch off the circuit breaker or unplug the unit if accessible.
2. Open the dishwasher door fully and remove the lower rack by pulling it straight out.
3. Locate the cylindrical filter assembly at the bottom of the tub. Rotate the filter counter-clockwise to the "Unlock" position and lift the entire assembly straight up.
4. Separate the coarse filter (the mesh cylinder) from the micro-filter (the flat disc) and rinse them under hot water to ensure no small debris is clogging the flow.
5. Use a high-intensity flashlight to inspect the sump cavity (the hole where the filter sits). Look for any visible glass shards or plastic fragments.
6. Reach your finger into the sump cavity to feel for obstructions. Be extremely careful, as broken glass is common here.
7. Locate the pump impeller—the small plastic fan blade at the bottom of the sump. Gently try to rotate the impeller with your finger. If it feels "gritty" or won't spin a full 360 degrees, there is an object wedged under the blade.
8. Use a pair of needle-nose pliers or a vacuum with a narrow attachment to extract the debris.
9. Reinstall the filter assembly, locking it firmly clockwise to ensure no further debris reaches the pump.
10. Run a "Quick Wash" cycle to verify the noise has ceased.

If That Didn't Work

• Check the Drain Pump: If the noise only occurs at the very end of a cycle or during the initial drain phase, the debris is likely in the drain pump rather than the wash pump. You will need to access the bottom of the unit by removing the toe kick panel and manually checking the drain impeller for obstructions.
• Inspect the Spray Arms: A loose plastic cap or a piece of debris trapped inside the lower spray arm can create a rhythmic buzzing sound as it rotates and hits the rack. Remove the lower spray arm by unscrewing the center nut and shake it to see if anything is rattling inside.
• Check for Leveling Issues: If the unit is not perfectly level, the pump can vibrate against the chassis, creating a low-frequency buzzing. Use a spirit level on the top frame and adjust the leveling legs until the unit is dead-level.
• Pump Motor Failure: If the grinding is metallic and constant regardless of debris removal, the pump motor bearings may have failed. This requires a full replacement of the wash pump assembly (Part #DC92-XXXXX depending on specific regional revision).

Heads Up

• Pre-Rinse Caution: While the Bespoke series has excellent filtration, always scrape large bones or hard seeds from plates. These are the primary culprits for pump impeller damage.
• Filter Maintenance: Clean the cylindrical filter assembly once every two weeks. A clogged filter forces the pump to work harder, increasing wear on the motor bearings.
• Glass Safety: Always use a flashlight and a tool (like pliers) when checking the sump; never use your bare fingers if you suspect broken glassware is the cause.
• Avoid Over-Sudsing: Using non-dishwasher detergents creates excessive foam, which can cause the pump to "cavitate," creating a buzzing sound that mimics mechanical failure.